Hacking

Counterstrike has been a prime target for exploitation by cheaters since its release, since then many different types of hacking has been created in the game. Some of them are:

• Wallhacks, which allow the player to see through walls. These work by altering the display driver to display objects that are normally obscured.
• Speedhacks, which give the player increased speed. These work by sending false synchronisation data to servers.
• No recoil, which keeps the players gun shooting straight on the x axis without a kickback by removing gun physics. No spread is used to make a players gun shoot straight along the y axis.
• Aimbots, which helps the player aim at enemies. These work by moving the player's view to anticipate an enemy's position.
• ESP, which shows textual information about the enemy, such as, health, name, and distance, and also information about weapons lying around the map, which could be missed without the hack
• Barrel hack, which shows a line that depicts where the enemy is looking
• Anti-flash and anti-smoke, which remove the flash bang and smoke grenade effect.
• Grenade Dodger, which moves player farther or closer to a grenade, depending on settings.

But Valve has implemented a cheat system called Valve Anti-Cheat(VAC) that will catch those hackers and their Steam accounts will be permanently banned from all VAC servers.

You can learn more about VAC here.