This is where I buy most of my games online. There are many more websites, but for better or for worse I'm just used to these three. Haven't had any major problem so far (fingers crossed). Disclaimer: I don't own any stocks in GamersGate, Good Old Games, Steam and Humble Bundle.
Sweden based GamersGate is a spin-off of Paradox Interactive, a games publisher. Dozens of games are regularly on specials, and the daily deal offers up to 75% off on some fairly recent titles. Big names and independent publishers compete with one another for your attention. Games can be downloaded without a client and minimal registration information is required to open an account. Keep an eye on sales of games at rock-bottom prices to be downloaded through Valve's Steam. Straightforward and easy, open a la Scandinavian, accessible from anywhere in the world. However, the site does not run as smoothly as GOG or Steam and occasionally has payment issues. GamersGate often runs out of serials leaving you stranded a few days before you can activate your game. Use only if the price is absolutely unbeatable and you don't mind waiting a little.
GOG.com used to known as "Good Old Games". There's nothing wrong with good ol' games for a good ol' gamer, but they must have changed their names once they started selling more recent titles. Based in Poland, Good Old Games brought back to the mainstream classic titles from the 1990s and beyond... The main particularity of GOG.com is that the games are sold without Digital Rights Management (DRM). From anywhere in the world, download, install on your computer, or another one, and yet another one, save back up copies on an external drive, on your cloud drive, do whatever you want since you've bought it already. The fact that most games are modified to work on the latest operating systems is a big plus. Fast download with a small client or "save as" directly to your disk. Great prices, easy to navigate website. Weekend and holiday specials are rightly popular.
Steam is owned by Valve Corporation, a US video game developer and distributor. With an estimated 70% of the $4 billion digitally distributed games market, more than 50 million users, and availability in 25 languages, Steam is one seriously big and busy mothership. Download requires a client software that manages digital rights. Once purchased, your games stay on your account and can be downloaded again on other machines. Although accessible from pretty much anywhere in the world, not all games and specials are available everywhere. The site is always buzzing and consequently sometimes a little slow. Fast internet is required, but the client does a good job at downloading your 10GB game over several days when your connection lacks juice. From the latest games to Beta versions, you are likely to find it here, at reasonable prices. There are daily deal, mid-week deals, weekend deals and special holiday sales.
The Humble Bundle store has raised more than US $5 million for charities. You can buy single games with a selection on store specials and weekly sale, but you can also pay what you want for a bundle or collection of games. Donate a portion of the purchase to your favourite charity from a list of over fifty to choose from. Humble Bundle is quick and easy to use. You don't even need to register if you think it's just a one off impulse buy. Games free of Digital Rights Management can be downloaded immediately after payment, while Steam codes are provided for other titles.
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