Cheats are often associated with multiplayer gaming these days, but it wasn't always that way. At one time, single player games were shipped with hidden cheat codes that could be used to unlock an array of nifty powers and shortcuts. Remember those days?

Back then, cheats were awesome. They didn't incite fury and animosity amongst gamers. Instead, they were there to help you get through the toughest games when you just weren't good enough, allowing you to experience content that you would have otherwise given up on.

Here are some of the most useful cheats to have graced video game history.

The Konami Code Cheat [Everywhere]

The Cheat: A sequence of input that goes Up, Up, Down, Down, Left, Right, Left, Right, B, A, Start. It's available in a number of Konami games and the cheat does something different depending on the game.

The History: The Konami Code is perhaps the oldest and most renowned cheat code in the world. It first existed in Gradius but was popularized by Contra, both games which were released on the NES. In the former, it granted a full set of powerups; in the latter, it granted 30 lives.

Today, the Konami Code button combo can come up in conversation to imply any sort of cheat, shortcut, or empowerment. The code is so well-known in the gaming community that other games - both Konami and non-Konami - tend to reference it in Easter eggs. For a full list, check out the Wikipedia page on Konami Code games.

Console Mode [Half-Life Cheats]

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The Cheat: Right click on the Half-Life shortcut and append -console to the end of the Target line. Start the game up and the menu will have a new option for accessing the console where you can type in various cheats.

The History: Most Valve games have a hidden way to access the console. Nowadays, the console is mostly used for quickly changing settings but Half-Life is notable for its available cheats. A simple phrase like notarget could render you invisible while noclip would let you fly through walls.

God Mode [Doom Cheats]

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The Cheat: Type iddqd. That's it.

The History: Doom is one of the more memorable games to employ cheat codes, likely because the success of Doom itself was a remarkable milestone in video game history. The fact that you could become fully invincible in a shooter game meant that you could tear down levels in the blink of an eye. It made you feel powerful.

Frankly, it was a lot of fun and most gamers who played Doom on God Mode can vividly remember their experiences doing so.

Rich Money [SimCity 2000 Cheats]

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The Cheat: Type buddamus or imacheat to receive $500,000 and all of the awards.

The History: SimCity 2000 wasn't the first simulation game to hit the market, but it sure was one of the most revolutionary ones. It showed that managing a city isn't as easy as it might first appear to be, which made this cheat code a welcomed tool for anyone who needed a bit of help.

SimCity was a true pioneer of the city-building genre. Ignoring the failed launch of SimCity 2013, the SimCity franchise is without a doubt one of the greatest simulation series of all time, spawning knockoff city-building games for Android and iOS.

Instant Win [Starcraft Cheats]

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The Cheat: Type there is no cow level and you will immediately win the current map.

The History:  Ah, Starcraft. It's one of a handful of games that have become so popular on an international scale that even non-gamers know of it. Strangely enough, the enigmatic "cow level" cheat code has roots in an earlier Blizzard game: the first Diablo.

In Diablo, there was a mysterious cow that purportedly opened up a secret level if the player clicked on it enough times. In Starcraft, Blizzard quelled those rumors with this cheat code. But it gets better! In Diablo II, Blizzard actually did implement a secret level full of cow-like enemies, resulting in an actual cow level. How's that for an Easter egg?

Going back to the actual cheat code, there is no cow level came in very handy for Starcraft players who wanted to experience the campaigns and take in the rich lore without needing to be skilled at the game.

Debug Mode [Sonic the Hedgehog 2 Cheats]

The Cheat: Navigate the Options menu and select Sound Test. Play the songs 19, 65, 09, and 17 in that order, then press Start. At the main menu, press and hold A, then press Start while still holding A. You'll see another Sound Test option. Play the songs 01, 09, 09, 02, 01, 01, 02, and 04 in that order. When you select a stage, press and hold A, then press Start.

The History: Okay, the instructions for this cheat code are convoluted and involved, but as it should be. This cheat code is more than just invincibility or speedy movement. This cheat opens up an entire new mode called Debug Mode, which allows you to edit stages, place items, and fly all over the place.

This is one of the most famous cheats simply because of how unique and interesting it is. It's like a whole new game.

Unlock Everything [Guitar Hero Cheats]

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The Cheat: At the main menu, press the Yellow, Orange, Blue, Blue, Orange, Yellow, and Yellow buttons in that order.

The History: Guitar Hero wasn't the first rhythm game but it succeeded in taking it to the next level. It's one thing to stomp on arrows with your feet. It's a much different (and arguably more fun) experience to jam on a guitar alongside your favorite rock songs.

Unfortunately, Guitar Hero forces the player into a progression by requiring songs to be unlocked through gameplay. That can be a big damper when all you want to do is play those still-locked songs that you love so much. With this cheat code, you can bypass all of the prerequisites and unlock everything instantly.

There are many other beloved cheats out there that have proven useful. What are some of your favorite cheats that you've used in the past to make your gaming sessions more enjoyable? Share with us in the comments!