Menu: Tools -> Options -> Debugging -> Edit and Continue
Did you know you can edit your code while you are debugging? You can do it with the Edit and Continue (EnC) feature. First, you can find this option under Tools -> Options -> Debugging -> Edit and Continue:
Also, there are a TON of language-specific scenarios where you can't use this feature which can be found here:
The caveats not withstanding, this is an interesting feature that allows you to edit code while you are debugging and continue execution without having to do a full recompile of the code.
I would be remiss if I didn't mention that there are some people who don't think using Edit and Continue is a good idea. John Robbins, whose opinion I respect a great deal, is one of those people and he makes some compelling arguments why you may not want to use this feature all the time. You can find John's post here:
Interestingly, you can find Jeff Atwood's rebuttal to John's argument here:
The bottom line: Make your own informed decision about using Edit and Continue but, even if you do use it, be fully aware of the implications of changes you make using it.