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What is the difference between a for loop and a while loop? And what about the for-in, do-while and for-each?
For Loops: When you know how many times you want to loop. When you are iterating through the indices of an array. When you have some sort of counter.
For-In Loops: When you are iterating over the properties of an object.
For-Each: When you want to iterate over the values of an object's properties.
While Loops: When you may be unsure of the number of times to loop.
When you want to loop while some condition is true.
Do-While Loops: When you want it to loop at least once before checking if the condition is true.
Intro to While Loops: Transcription
Let's say I wanted to write something out on the screen ten times. I could go ahead and be boring and type out document.write and type in whatever, like "this is a sentence" or something.
I could copy and paste it ten times and that would be fine. It would run. But that's not very efficient. I've wasted ten lines of code in my text editor.