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The "Incrementing" Lesson is part of the full, Introduction to JavaScript course featured in this preview video. Here's what you'd learn in this lesson's course:

Brian gives examples of various ways to increment values in JavaScript.

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Transcript from the "Incrementing" Lesson

>> Brian Holt: So what I wanted to show you are all the different ways you can do incrementing a number by 1. So friendsAtYourParty += 1. This is saying add 1 to friendsAtYourParty and reassign it. As you might imagine, you could put 5 here and it would add 5 and reassign that, right?

So that would be the same as this.
>> Brian Holt: Line 4 and line 5 are doing exactly the same thing right now.
>> Brian Holt: And this works with all of the operators. You can do -=, it'll subtract 5 from it, you can do *=. And the way you do times in JavaScript is with the star.

And /=, which is division. I don't if you ever seen anyone use /=, but it's there. There's also friendsAtYourParty++, like C++, right, we've heard of that. That's because it's 1 better than C, that's joke, right?
>> Brian Holt: Computer scientists have bad sense of humor. So this will take friendsAtYourParty and increment it by 1.

You can also do ++friendsAtYourParty, that also works.
>> Brian Holt: So I'll put this back to 1. All of these do exactly the same thing. Adds 1, adds 1, adds 1.
>> Brian Holt: Now I will say that in JavaScript, I don't see anyone do ++ and then the name of the variable.

This is just,
>> Brian Holt: No one ever does it this way. You can, but people don't. People always do ++ on the end, postfix.
>> Brian Holt: Okay, reason why I show this is cuz the next example is going to use this.