Nápady Atom Y

Nápady Atom Y. May 12, 2016 august 28, 2016 the nexus 9 comments. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Why some things are heavy and others are not? Atoms are extremely small, typically around 100 picometers across.

Tady Use The Table To Determine The Number Of Protons For Each Atom Then Choose The Statement Below Brainly Com

They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. May 12, 2016 august 28, 2016 the nexus 9 comments. Why some things are heavy and others are not? Atoms are extremely small, typically around 100 picometers across. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms.

Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.

Why some things are heavy and others are not? Ever wonder why how there are so many different substances in the universe and what makes them different from each other? May 12, 2016 august 28, 2016 the nexus 9 comments. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Atoms are extremely small, typically around 100 picometers across. Great things happen when developers work together—from teaching and sharing knowledge to building better software.

Ever wonder why how there are so many different substances in the universe and what makes them different from each other?.. Why some things are heavy and others are not? They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. May 12, 2016 august 28, 2016 the nexus 9 comments. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.. Ever wonder why how there are so many different substances in the universe and what makes them different from each other?

May 12, 2016 august 28, 2016 the nexus 9 comments... They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Atoms are extremely small, typically around 100 picometers across. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Why some things are heavy and others are not? May 12, 2016 august 28, 2016 the nexus 9 comments.. Ever wonder why how there are so many different substances in the universe and what makes them different from each other?

Great things happen when developers work together—from teaching and sharing knowledge to building better software. Atoms are extremely small, typically around 100 picometers across. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor... Why some things are heavy and others are not?

An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across.

Great things happen when developers work together—from teaching and sharing knowledge to building better software. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Atoms are extremely small, typically around 100 picometers across. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Great things happen when developers work together—from teaching and sharing knowledge to building better software. May 12, 2016 august 28, 2016 the nexus 9 comments. Why some things are heavy and others are not? Great things happen when developers work together—from teaching and sharing knowledge to building better software.

Ever wonder why how there are so many different substances in the universe and what makes them different from each other? . Great things happen when developers work together—from teaching and sharing knowledge to building better software.

They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Ever wonder why how there are so many different substances in the universe and what makes them different from each other?

Atoms are extremely small, typically around 100 picometers across. Atoms are extremely small, typically around 100 picometers across. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Why some things are heavy and others are not? Great things happen when developers work together—from teaching and sharing knowledge to building better software. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? May 12, 2016 august 28, 2016 the nexus 9 comments. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms... Atoms are extremely small, typically around 100 picometers across.

May 12, 2016 august 28, 2016 the nexus 9 comments.. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.

An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Why some things are heavy and others are not? They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Atoms are extremely small, typically around 100 picometers across. Ever wonder why how there are so many different substances in the universe and what makes them different from each other?.. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects.

Ever wonder why how there are so many different substances in the universe and what makes them different from each other? They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Atoms are extremely small, typically around 100 picometers across. Why some things are heavy and others are not? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. May 12, 2016 august 28, 2016 the nexus 9 comments. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Ever wonder why how there are so many different substances in the universe and what makes them different from each other?

Why some things are heavy and others are not?.. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. May 12, 2016 august 28, 2016 the nexus 9 comments.

Great things happen when developers work together—from teaching and sharing knowledge to building better software... Atoms are extremely small, typically around 100 picometers across. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms... Ever wonder why how there are so many different substances in the universe and what makes them different from each other?

Atoms are extremely small, typically around 100 picometers across. Why some things are heavy and others are not? May 12, 2016 august 28, 2016 the nexus 9 comments. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.. Atoms are extremely small, typically around 100 picometers across.

Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. May 12, 2016 august 28, 2016 the nexus 9 comments. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Why some things are heavy and others are not? Atoms are extremely small, typically around 100 picometers across. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects... May 12, 2016 august 28, 2016 the nexus 9 comments.

They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects.. May 12, 2016 august 28, 2016 the nexus 9 comments. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Why some things are heavy and others are not?. Why some things are heavy and others are not?

Great things happen when developers work together—from teaching and sharing knowledge to building better software. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Why some things are heavy and others are not? May 12, 2016 august 28, 2016 the nexus 9 comments. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.

An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Why some things are heavy and others are not? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.

Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Great things happen when developers work together—from teaching and sharing knowledge to building better software. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. May 12, 2016 august 28, 2016 the nexus 9 comments. Why some things are heavy and others are not? Ever wonder why how there are so many different substances in the universe and what makes them different from each other? An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Atoms are extremely small, typically around 100 picometers across. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.

Great things happen when developers work together—from teaching and sharing knowledge to building better software. May 12, 2016 august 28, 2016 the nexus 9 comments. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. May 12, 2016 august 28, 2016 the nexus 9 comments.

Atoms are extremely small, typically around 100 picometers across. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Why some things are heavy and others are not? They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. May 12, 2016 august 28, 2016 the nexus 9 comments. Great things happen when developers work together—from teaching and sharing knowledge to building better software. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across. Atoms are extremely small, typically around 100 picometers across.

Atoms are extremely small, typically around 100 picometers across. May 12, 2016 august 28, 2016 the nexus 9 comments. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Atoms are extremely small, typically around 100 picometers across. Great things happen when developers work together—from teaching and sharing knowledge to building better software. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Why some things are heavy and others are not?. Why some things are heavy and others are not?

Why some things are heavy and others are not?.. Great things happen when developers work together—from teaching and sharing knowledge to building better software. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Why some things are heavy and others are not? Ever wonder why how there are so many different substances in the universe and what makes them different from each other? May 12, 2016 august 28, 2016 the nexus 9 comments. Atoms are extremely small, typically around 100 picometers across.. Why some things are heavy and others are not?

Atoms are extremely small, typically around 100 picometers across. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Why some things are heavy and others are not? Atoms are extremely small, typically around 100 picometers across. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. May 12, 2016 august 28, 2016 the nexus 9 comments. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.

Great things happen when developers work together—from teaching and sharing knowledge to building better software.. Why some things are heavy and others are not?

Great things happen when developers work together—from teaching and sharing knowledge to building better software. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects.. Ever wonder why how there are so many different substances in the universe and what makes them different from each other?

Ever wonder why how there are so many different substances in the universe and what makes them different from each other? They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Atoms are extremely small, typically around 100 picometers across. May 12, 2016 august 28, 2016 the nexus 9 comments.

Great things happen when developers work together—from teaching and sharing knowledge to building better software.. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Ever wonder why how there are so many different substances in the universe and what makes them different from each other?. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms.

Atoms are extremely small, typically around 100 picometers across. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Great things happen when developers work together—from teaching and sharing knowledge to building better software. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Why some things are heavy and others are not? Ever wonder why how there are so many different substances in the universe and what makes them different from each other? May 12, 2016 august 28, 2016 the nexus 9 comments... May 12, 2016 august 28, 2016 the nexus 9 comments.

Ever wonder why how there are so many different substances in the universe and what makes them different from each other?. Why some things are heavy and others are not? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Atoms are extremely small, typically around 100 picometers across. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects.

Great things happen when developers work together—from teaching and sharing knowledge to building better software... An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms.

May 12, 2016 august 28, 2016 the nexus 9 comments... Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects... Great things happen when developers work together—from teaching and sharing knowledge to building better software.

An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms.. Why some things are heavy and others are not? An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.

They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects.. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms.. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms.

Atoms are extremely small, typically around 100 picometers across... . Great things happen when developers work together—from teaching and sharing knowledge to building better software.

Why some things are heavy and others are not? Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Atoms are extremely small, typically around 100 picometers across. Great things happen when developers work together—from teaching and sharing knowledge to building better software. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms.. Why some things are heavy and others are not?

An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. May 12, 2016 august 28, 2016 the nexus 9 comments. Why some things are heavy and others are not? Great things happen when developers work together—from teaching and sharing knowledge to building better software. Atoms are extremely small, typically around 100 picometers across. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.

Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? May 12, 2016 august 28, 2016 the nexus 9 comments. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Why some things are heavy and others are not? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.

They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects.. Why some things are heavy and others are not? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Great things happen when developers work together—from teaching and sharing knowledge to building better software. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across. May 12, 2016 august 28, 2016 the nexus 9 comments. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Ever wonder why how there are so many different substances in the universe and what makes them different from each other?. Why some things are heavy and others are not?

Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Atoms are extremely small, typically around 100 picometers across. Great things happen when developers work together—from teaching and sharing knowledge to building better software. May 12, 2016 august 28, 2016 the nexus 9 comments. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Why some things are heavy and others are not?.. May 12, 2016 august 28, 2016 the nexus 9 comments.

They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects.. Why some things are heavy and others are not? Ever wonder why how there are so many different substances in the universe and what makes them different from each other? May 12, 2016 august 28, 2016 the nexus 9 comments. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Great things happen when developers work together—from teaching and sharing knowledge to building better software. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across. Atoms are extremely small, typically around 100 picometers across.

Why some things are heavy and others are not? Ever wonder why how there are so many different substances in the universe and what makes them different from each other? They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. May 12, 2016 august 28, 2016 the nexus 9 comments. Atoms are extremely small, typically around 100 picometers across. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Why some things are heavy and others are not? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor... Why some things are heavy and others are not?

Atoms are extremely small, typically around 100 picometers across. Why some things are heavy and others are not? An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Great things happen when developers work together—from teaching and sharing knowledge to building better software. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Atoms are extremely small, typically around 100 picometers across.

Great things happen when developers work together—from teaching and sharing knowledge to building better software... Great things happen when developers work together—from teaching and sharing knowledge to building better software. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? May 12, 2016 august 28, 2016 the nexus 9 comments. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Why some things are heavy and others are not?. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.

Why some things are heavy and others are not?.. Atoms are extremely small, typically around 100 picometers across. An atom is the smallest unit of ordinary matter that forms a chemical element.every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Great things happen when developers work together—from teaching and sharing knowledge to building better software. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Why some things are heavy and others are not? Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor.

Ever wonder why how there are so many different substances in the universe and what makes them different from each other?. They are so small that accurately predicting their behavior using classical physics—as if they were tennis balls, for example—is not possible due to quantum effects. Teletype for atom makes collaborating on code just as easy as it is to code alone, right from your editor. Ever wonder why how there are so many different substances in the universe and what makes them different from each other? Atoms are extremely small, typically around 100 picometers across. Ever wonder why how there are so many different substances in the universe and what makes them different from each other?