The show is a three-day gaming orgy
Thousands of keen gamers are gathering in Los Angeles for the industry's annual jamboree, the Electronic Entertainment Expo, known as E3.
E3 is where video game companies showcase their line-up for the coming year, including games that are still being developed.
Among the games drawing the biggest buzz before the show are the PC shooters Doom III and Half-Life 2, as well as console titles Gran Turismo 4 and Halo 2.
Ahead of the show, there has been speculation of a further drop in the price of consoles, though some analysts doubt whether this will happen.
E3 is a three-day entertainment extravaganza, with more than 60,000 people rushing to get their hands on the latest games.
Many sequels, like Doom III, will be on show
The show officially opens on Wednesday but the event kicks off today with Microsoft expected to announce upgrades to its online gaming service, Xbox Live.
Since launch in November in the US, Xbox Live has attracted about 500,000 subscribers.
Microsoft is also expected to give more details about Halo 2, the sequel its best-selling Xbox title. The sci-fi first-person shooter has sold almost three million copies.
Rivals Sony and Nintendo have also lined up pre-show events to showcase the latest games for their consoles, the PlayStation 2 and GameCube.
The PlayStation is the undisputed console king. Sony has sold more than 50 million PS2s worldwide, compared to about nine million each for the Xbox and GameCube.
Last year, Sony used E3 to announce a fall in the cost of its console, spurring Microsoft and Nintendo to follow suit.
Many in the games industry are holding their breath to see if this will happen again this week, as it would help to boost game software and hardware sales.
Aside from the hardware, sequels and movie spin-offs are likely to attract the most attention from gamers.
Enter The Matrix game is expected to attract plenty of attention
More than 1,350 titles from 400 companies will be on display.
Aside from Halo 2, Half-Life 2 and Doom III, highlights include the latest Tomb Raider title, Angel of Darkness, and follow-up to the best-selling god game, The Sims.
The gaming companion to The Matrix Reloaded movie, Enter the Matrix is likely to attract much interest, as is the next spin-off from the Lord of the Rings series, Return of the King.
Mobile gaming will also get a look-in during E3. Nokia is due to reveal more information about its N-Gage gaming mobile and game publishers such as Sega are set to show off new titles for mobiles.