Why?: LAN parties allow the people involved to play multi-player (as opposed to single-player against the computer) games at higher speeds than normally avaiable on the internet. Also, being able to see the look on people's faces when you kick their asses is fun to watch. Its a bit of work to unhook your computer, take it to another person's house, and set it up again, but its most definitely worth it.
Time: Usually LAN parties take place starting around 6pm, and ending at whatever time you get tired... later than 4AM.
Games:A variety of games are played covering genres such as FPS (first person shooter), RTS (real time strategy), and RPG (role playing game), however FPSs are most common and popular.
Food: During the typical LAN party a large quantities of soda, fatty/sugary snacks, and pizza(or some similar product) are consumed.