100 Episodes is the point at which a TV series typically becomes viable for syndication.

Once the series has achieved 100 episodes, the show can be played 5 times a week for 6 months without any repeats. Usually this point occurs at some time within the 5th season.

I looked into this because I noticed that USA now has House in syndication. It didn’t seem to me like there were enough episodes for that, but it turns out House had its 100th episode about 6 episodes ago.

The practice of running a formerly weekly show 5 times a week is called stripping. Which will explain my next post…

Source: wiki