Quote Originally Posted by JackHatchet View Post
snip
It's an overlay that displays data taken from the game, a separate window that you can put anywhere on screen. Most common use of it is to simply display DPS or HPS numbers and taking the logs to upload to FFLogs, etc. There are additional things that it can also do, such as notify you that a certain world boss is in the area, for example. It doesn't tell you where specifically, just that it's somewhere in the zone or your general vicinity if it's an A rank mob or lower.

Another, more controversial, feature of ACT is to have a robot lady tell you when a boss is casting something. One side of the spectrum argues that it makes the game easier and gives you an advantage, but you have the other half of the people saying otherwise because all it's doing is vocalising the information that you can readily see but might miss due to tunnel visioning. But this probably only ties into a minority of the community. There is no such thing as it "hacking" into the game, unless you have a different definition of hacking; it takes data you can already see and simplifies it.

Modding, which is what this thread was originally about, doesn't use ACT and, in a sense, I guess it could be considered "hacking"? But really, modding is just replacing files from the game folder and it's entirely client side.