Comments are a crucial part of well-written code. They can document the function of different elements of a site, which can be invaluable as you are learning code and may be prone to forgetting what different parts of your file are for. They also can be used to temporarily eliminate portions of your code that are not working correctly, which may be helpful as you troubleshoot problems. Finally, in advanced coding, comments are used to communicate with other web technologies - you may not need to know this now, but if you find comments that look a lot like computer code elsewhere on the Web, it may prove useful. Keep in mind however, that comments are delivered with the functioning code, so they are available to any curious user who looks at the source code for a website.