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Hello and welcome to this leg shot in this lecture.

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I'll be talking to you about variables in the Ruby programming language.

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What is a variable variable.

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Basically is a memory location.

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Irish place that holds any day tiny piece of data that can be use by a program or any program.

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It variable is also a name that Ruby associates with a particular object variable names should be lower

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case whereby you have variable names that contains two word is best to use an underscore to separate

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the words.

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For example he may have a variable called Order mount.

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Bessie is an on the score to separate the words.

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Unless you intend to give it it's just one word.

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In that case you can call it total for example variables in Ruby can contain any data types so you can

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have a string or an integer.

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Also when you name your variable give them common sense names that reflect what the variable doors or

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what day to day hold or store.

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You can not use reserved names in the Ruby programming language for variable names for example you can

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call it variable class method on module.

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These are all reserved words that are already used in the Ruby programming language.

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These are just a few examples.

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If you want a detailed example Reserve word you have to reference the ruby documentation variables in

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themselves and not object by references to objects in the Ruby programming language before you can use

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a variable.

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You must assign or give you the value variable that hasn't got good value is referred to as on defined.

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What is an assignment and assignment basically is some operator that is used to give variables in value.

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Okay.

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Usually you identify that with the symbol the symbol for an assignment operator is equal to say.

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So let's take a look at a couple of examples.

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First here I've got a variable called X..

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We've signed it off 7 0 got another variable cuong greeting me assigned it to a value of Hello.

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So let's say you use the assignment operator.

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I've got my interactive Ruby open.

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If you on a Windows This is located in your ruby fault in our program.

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If you are on here Linux or a Mac just type in our being in your temin or shell that should give you

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access.

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Let's create some variables.

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And when I create a variable context and give it a value of 7 I create on a pillow variable call.

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Why I give this value or if I create another one chord set and then give this the value would be x plus

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why that give 15.

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So if I type in there is to output 15.

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You can also change the value of a variable once you've assigned to value for example I can come here

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and change decks to ecorse to instead of being 7.

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I can make x 15.

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So now I can see the Z course to X class Y.

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That will no longer give me 15.

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Now what is it all value.

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This should now change and give me twenty three so if I type in there the new value for Z is 23 so you

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can always change the value once you've given a variable name.

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So let's create another variable.

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Core is greeting.

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Can I just give you a valley of say hello.

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So if I want a reference that I just typing puts followed by the word greeting and that does give me

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hello.

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So if I wanted to change the value of that greeting I just can't taiping greet in ecorse too.

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How are you.

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Okay.

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Now if I'm typing greeting I should get how are you.

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So why should you assign values you can always change them so feel free to experiment creating.

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Boer's a sign of a bad to that.

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So that's it for this lecture.

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On their reports.

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Many thanks for watching.

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Bye for now.