This was the first real Battlefield game, and the one that founded our love for the series. Below is the wikipedia entry for the game.
Battlefield 1942 is a first-person shooter video game developed by Digital Illusions Creative Entertainment and published by Electronic Arts for Microsoft Windows and Mac OS X. The game can be played in single-player mode against the video game AI or in multiplayer mode against players on the Internet or in a local area network. It is a popular platform for mod developers, with a large number of released modifications that alter the gameplay and theme.