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Hello and welcome.

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In this video I will explain what expressions are in computer programming.

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What is an expression an expression is any reference to a variable or value or a set of variables and

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values combined with operators.

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A variable is basically a container that is used to store values which the program we use and values

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are represented by different types of data structures.

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For example a number like number 7 is a value a boolean value boolean values are values that are either

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true or false.

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So there can only be two outcomes.

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Those are known as boolean values.

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Also a collection of text which is also referred to as a string data type so it's like the text characters

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strong like a string.

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So they're referred to as a string in programming.

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So also you have operators for example the addition operator multiplication operator assignment operators

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all these combined together on what is used to refer to as an expression computer program is basically

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a bunch of statements and statements are made up of one or more expressions.

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So let's take a look at a very basic expression it's a complete statement.

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This is known as a statement in programming.

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This here is a javascript statement.

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So this statement basically has a full expression inside it.

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We've got the seven.

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This is known as a literal value expression.

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So the number seven is referred to as a literal value expression.

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The bee is known as a variable expression which means it basically retrieves its current value.

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OK.

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So a verbal expression is used to retrieve its current value.

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The B times seven is known as an error rate meant.

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Expression which means it's basically doing something so is multiplying this so b times seven basically

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means you're multiplying the value of this by seven.

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So that's referred to as an error rate metric expression the value a equals b times two is known as

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an assignment expression this equals two.

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Here is an assignment expression which means it is used to assign the result of b times seven to the

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variable e.

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OK.

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So anyway you see an equals to sign is known as an assignment expression.

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It is used to place a value inside a variable this here b times seven.

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This is an expression that basically stands alone.

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And it is referred to as an expression statement so expressions are an important part of computer programming.

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So when you are writing your statements for your computer programs they are also used to write the statements

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whenever you use your right statement.

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You must include various type of expressions.

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So that's it for this introduction to expressions.

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Thanks for watching.

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Bye for now.