Well, Mitchell, there are a lot of reasons why this could be. The most common answer is the Kindle simply isn't charged. Find a micro USB cord and plug your kindle in.
Other reasons why your kindle won't turn on are more serious problems such as battery or motherboard failure. Don't fret because you can figure out how to [guide|37825|replace the battery] and [guide|37917|replace the motherboard here]!
[[Kindle 7th Generation Troubleshooting|Be sure to head over to trouble shooting to narrow the problem down!]]