This thread is basically a copy of the thread made sometime ago by Konato_K regarding the different types of hacks and such. I've remade it so we can have a copy of it here on the new forums and it also helps people to understand the different types of hacks that are used.

#1 » [forcefield/killaura]
Almost everyone knows these hacks and it basically adds a magical forcefield around the user, this forcefield is able to hit every living entity (or players) that is around in their reach limit (such things as reach hacks do not exist, it is either forcefield or click aimbot),which depending on the configuration of NoCheatPlus (a plugin to prevent cheating in the servers) this can be reduced so a player can hit in every single direction but not as fast as they would normally, or a player that really can't hit anyone out of his sight of view (as said, this depends on the NoCheatPlus configuration).
It's a very common hack and easy to notice, the fastest way to know if someone has it is if they are able to hit a player from the back.

#2 » Sprint Hacks
This hack is pretty easy to identify, if you have the right eye. Sprint hacks basically allow your player to run at different speeds without stopping. For example, Nodus's sprint hack makes it so that you can run at 2 bars of hunger and increase your run speed by 1.5. If you notice sprint particles below someones feet while they are standing still, they are sprint hacking. If they run into a block and do not stop sprinting that is also usually sprint hacking (or clumsiness). The particles on their feet can also be caused by lag, so, try to not think someone is hacking when you see it.

#3 » Fly Hacks
This doesn't need to be explained - basically it lets you fly. There are also some forks like glide or things like that, but is basically the same.

#4 » Step
This is a really hard hack to identify. Basically what step does is allow the hacker to treat any block as stairs, whether it be fences, blocks, and in rare cases, 2 high blocks, they can simply walk though it making them incredibly hard to chase. There are 3 levels of step.
Step 1 » Allows you to go up blocks that are 1 high.
Step 2 » Allows you to go up blocks that are 1.5 high.
Step 3 » Allows you to go up block that are 2 high.

#5 » Spider
This is similar to the step hack, except it treats every block as a vine. Yep. They can climb up a 100 block wall easily. Most block glitchers have this hack since they can simply climb up a 3 block barrier. These are hard to identify since they usually do it really fast.

#6 » X-ray
We probably all know this one. So I will not explain it. :p

#7 » Free Cam
This hack is really dangerous. It allows the hacker to "Leave" their body and explore while flying. You cannot see this "Ghost" but you can see the hacker just standing in a concealed spot doing nothing, occasionally moving his hand to destroy blocks in his ghost form. These are pretty hard to identify.

#8 » Player Esp
This hack allows you to see a bright red box around all players, so, they are able to see every player even underground or in the air, it's basically impossible to notice, and its used normally with xray.

#9 » BreadCrumb
This hack creates lines where people have walked, allowing the hacker to see "Bread Crumbs" of what an escaping player might have left behind.

#10 » Tracers
This hack draws a line straight to wherever any player or chest is. For example lets say you are tunneling. All of the sudden, a hacker falls in from the top. He found you by this hack. It pointed a straight line to wherever you were that updates in real time.

#11 » FullBright
This is not really a hack but is actually something that can be changed in the configuration files of minecraft (and therefore, can be used in vanilla), it basically lets you see in the dark as it has light level of 15 (the maximum, or day). You'll find that we don't allow this on nearly all of our servers.

#12 » NoFall
Basically this allows you to not take any damage when falling so they can virtually go skydiving anywhere.

#13 » Waterwalking
This hack allows you to walk on water as if it were a block, while making particles appear as if you were swimming on the water. But it is very easy to detect.

#14 » Aimbot [playeraimbot or clickaimbot]
This basically makes your player aim automatically at your opponent so that you can just click away and still get kills.

#15 » Bow Aimbot
This is aimbot but for bows, it also targets teammates so that's a big giveaway if anyone is using it or not.

#16 » FastBreak
This allows you to break blocks a lot faster than normal. You can tell if they are using this hack if they break blocks really fast like obsidian etc.

#17 » AutoBuild
Makes you auto-magically place blocks. You will get kicked by a vanilla minecraft server for placing blocks too fast.

#18 » Nuker
This auto-magically breaks blocks around you.You will get kicked by a vanilla minecraft server for breaking blocks too fast. However, it is possible.

#19 » FastClick
This doesn't need any explaining as to what it does.You can notice it because the player can place blocks insanely (or hit insanely), in the case of blocks, you can know it by the sound, if it was lag, all the blocks sound at the same time, but this sounds like a machine gun really fast.

#20 » AutoTool
This is an extremely hard hack to detect and is very overpowered. It automatically switches to the right item in your inventory when you need it (i.e. you hit someone with nothing in your hand but a sword in your inventory, it puts the sword in your hotbar and switches to it when you hit someone.)

#21 » AutoPotion/Eat
This is similar to AutoTool, but automatically drinks potions when you need them. It switches to the one you need, for example, if low on health, to health potions or regeneration potions and automatically drinks/ throws them on yourself. It has been done with food and it works in the same way.
Very hard to detect.

#22 » AutoArmor
This explains itself - if you have a good eye this is easily spotted if a player picks up armor items and instantly equips them.

#22 » NoSlowDown
This hack allows the user to keep running when drinking, eating or running with the bow drawn.

#23 » FastBow/RapidFire
In the history of CR this is one of the older hacks and isn't really seen anymore but it basically allows a user to fire arrows at a fast rate.

#24 » Auto-Things
This is not the name of a particular hack but here is a list of every hack/mod/bot or method to make some minecraft functions automatic, this includes;
» Automatic criticals - jumping and clicking too fast.
» Autimatic walk
» Automatic spam bots - being able to crash a server if spam too fast, however, this doesn't work on CR.

#25 » AntiKnockback
This is very common in most servers and is something dealt with on the daily. It simple allows the user to not take knockback when they are being hit.

Now, I'll make a list of things that can not be used, due to the way the server to client works or other things, to avoid any big explanations I'll just say that these things are handled server-side and as such there is no way to make hacks that can do this, there are ways to confuse or make it appear to work like those listed below, but is not what it looks like.

God hacks » The user cannot be hit.
Knockback hacks » The reverse of antiknockback - this would give more knockback to anyone you hit.
Fast regeneration
Damage hacks » The user deals more damage.
Reach hacks » Allow the user to hit from a further block distance.
Permission hacks » Getting more permissions in a server.
Inventory hacks