Valve experimented with episodic games with half life. The idea was to release small, couple hour episodes as a continuation of the story frequently, instead of

Valve experimented with episodic games with half life. The idea was to release small, couple hour episodes as a continuation of the story frequently, instead of waiting a long time to make a half life 3. Clearly that didn't happen. What you need to know is that it's more campaign for half life 2. If HL2 is a movie, episode one is the first episode of the TV show. Smaller, but still good.