If the PlayStation Network existed only as an online marketplace in the form of the PlayStation Store, Sony never could have come close to rivaling the success of Microsoft's Xbox Live. Online gaming forms the backbone of PSN, and all of its other features radiate out from that all-important starting point. Online gaming on PSN is completely free -- and ever since Sony released its landmark firmware update (2.4) in mid-2008, the XMB has been available in all PlayStation 3 games at the press of the PlayStation button on the controller [source: PlayStation Blog]. That was a big deal for PSN gaming, because for the first time it meant gamers could easily switch between games, view their friends lists, and send text messages to those friends. For most people, playing games online is about playing with friends. Before that update, keeping in touch with other PS3 users wasn't exactly easy.
Sony has consistently made PSN gaming more accessible, but the actual gaming experience has more to do with the game itself than Sony's network. For example, certain PS3 games -- often first-party games published by Sony, like "Warhawk" and "M.A.G." -- provide players with dedicated servers that host online games. Most of the time, however, game developers do not provide dedicated servers but instead use a networking infrastructure that chooses a certain player's connection to host the game. This can introduce a discrepancy between players in an online gaming match -- essentially the host console is The Boss. Players far away from the host or players on a slow connection may experience high latency, leading to lag in their games. The host console will never experience these effects, which sometimes can lead to a host advantage [source: Bungie]. The vast majority of online games on consoles use this technology, but but the effectiveness of the "netcode" varies from game to game.
Sony added another major feature with firmware update 2.4 that emulated one of Xbox Live's most popular concepts. Sony launched Trophies, the PlayStation counterpart to Xbox Achievements, which reward players for certain in-game activities. Finishing a game on a high-difficulty setting, scoring a certain number of kills in online multiplayer and other achievements unlock PlayStation Trophies gamers can show off to their friends or enjoy themselves as dedicated completionists. And that's the gist of gaming on PSN. Next up: Let's look at how to download and buy games, movies and other media from the PlayStation Store.