What is a Wabbit?
A Wabbit is very uncommon to encounter, one of the reasons is they don't spread to other computers by itself. Once a wabbit is executed it start to replicate itself real quick, hence the name, creating lots and lots of files on your computer causing your harddrive to be filled up and system unstability.
Some wabbits are a little more advanced and start copies of the newly created files, thus creating more wabbits in an exponential way,t aking up more harddrive space, pushing your CPU and memory and, finally, crashing or freezing your computer. Wabbits are annoying but not that harmfull, unless more malicious code is added but then a wabbit isn't a wabbit, but it turns into a virus.
You get a wabbit the same way you get other malware, bad protection or unsafe surfing, to remove one, go here. And to prevent problems in the future go here.