Summer is in full swing, and that means it's time for the Steam Summer Sale, the biggest PC gaming event of the year. From now until July 4, thousands of games will be on sale via Valve's digital gaming platform.

Kicking off the sale are steep discounts on a number of popular game franchises. The Sonic the Hedgehog franchise, which is celebrating its 25th anniversary this year, is 50 percent off, and the ever-popular Call of Duty series is 50 to 67 percent off. All LEGO video games are 30 to 75 percent off, as is the Assassin's Creed franchise.

The Steam Summer Sale is also a great time to pick up a number of the more popular indie games that have been released in the past year. The wildly popular Harvest Moon-style farming game Stardew Valley is currently at 20 percent off for $11.99, while the brutally difficult dungeon-diving simulation Darkest Dungeon is at 40 percent off for a price of $14.99. This War of Mine, a game about civilians struggling to survive during wartime, is at 75 percent off with a price tag of $4.99. RPG darling Undertale is currently discounted 30 percent for a price of $6.99.

And that's barely scratching the surface of the massive sale. Usually some kind of minigame or event goes alongside the sale, but it appears this year Valve is keeping things simple. This time around, players simply earn Summer Sale trading cards by buying games or discovering games through their personal queues each day. Those cards can then be turned into badges that can be featured on a user's profile and goes toward increasing a user's Steam level. Players can also sell cards on the Steam marketplace.

Sales of years past have also featured daily deals and flash sales that would expire after a certain period of time. That doesn't look to be the case this year. Everything on sale appears to be on sale for the duration of the event, so fans don't have to wait for a game they are wanting to be featured on a daily deal in order to pull the trigger. It's yet another way Valve appears to be simplifying the event.

Because of the huge levels of traffic, the Steam store is currently experiencing a number of issues loading. That's to be expected, and should fix itself once players stop swarming the Steam servers to check out all the new deals.