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Now, before we dig deeper into variables

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and different values and what we can do,

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let's talk about the general syntax of all of that again.

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You've learned about some important syntax features

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and rules already.

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For example, that there must be a white space after let

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and that let is a special keyword in JavaScript,

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which we can use to instruct the browser

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to create a variable.

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We learned that we then can store a value

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with help of the equal sign in that variable and,

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very important for that variable name,

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that it must not contain any blanks or special characters

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and that we therefore typically use this convention

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for giving it a name.

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The difference between a rule and a convention

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is that a convention is not a must to do,

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a rule on the other hand is.

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So it's a rule to not have blanks,

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but a convention to then use this camelCase notation

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for assigning that name.

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You could also set it to greeting texts like this,

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starting with a capital G, that would be valid,

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it would not violate any rules,

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but it would be against this convention.

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So that's why I'm following it with a lowercase G.

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Now another syntax feature,

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which you will see in a lot of JavaScript code,

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including my JavaScript code from now on

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is that lines end with a semi colon.

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It's actually not a must to do,

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as you can clearly tell by the fact

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that this code worked without issues,

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but it is something which is often done.

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It's done to clearly mark, where a line of code ends.

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Now, of course you could say, well,

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obviously the line ends where it ends,

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but theoretically, in JavaScript,

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you are allowed to have multiple commands in one line,

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but without a semi-colon you would get an error,

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as you can tell.

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If I add a semi-colon here, that would work again.

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Now it's not considered a good practice

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to put multiple instructions into one line though.

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And therefore you typically should split them across

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multiple lines and hence,

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you can omit semi-colons.

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Nonetheless, since we must use semi-colons

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in many other programming languages,

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and since you must use them in JavaScript

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if we had multiple instructions in the same line,

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it's often seen that people do use semi-colons

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after every line,

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even if they do split their code

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across multiple lines correctly.

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And it's also something, a certain programming style,

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which I like to follow and therefore,

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I also put semi-colons at the end of each line,

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but it's technically not required

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and you don't have to do it,

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but if you don't do it, you should never do it.

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So again, be consistent, just as with the quotes.

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You can create strings

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with double or single quotes around them,

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but you should be consistent once you've made a decision.

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And here I will be consistent

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and I will be using semi-colons

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at the end of every code line.