Just googled Automacro and found it on a WOW Exploit site.

One explanation of how it can be used (Without the code, to keep people out of trouble) is a one button Druid heal..... as follows

This macro essentially turns Druid healing into one button.

It checks if Rejuv is on the target, if not it casts it, checks for Abolish Poison,

if not it casts it, if their life is below 75% it will pop Swiftmend,

and it then checks if you have 3x stacks of Lifebloom. All with one macro.
Things like this used to be possible, but was nerfed by Blizzard for whatever reason.

Thanks to AutoMacro you can do it again.

So, this is DEFINETLY illegal