It sounds like a swear word, but what it means is the causing of fractures in a rock layer by pressurised fluid. This then releases - among other things - petroleum, that we then can burn to run our cars. Yay. Well maybe. There are those for and those against. What I hate about anything like this is objectivity goes out the window as vested interests defend their cause. So is it good or bad?
Positive: Cheaper petrol and an extended use of this fuel type. This reduces the dependence on present oil producers which make up OPEC.
Negative: Risk of underground water supplies being contaminated. Possible increase in earthquakes.
Summary: Apparently with adequate precautions and care, risk of pollution can be minimised. As for increased earthquake activity, it is unfortunately impossible to know.
The facts are: 1) Our cars will increasingly be burning fuel from fracking. 2) The need to find new pertol sources will drive fracking forward whether there are risks or not. 3) R & D spent by car makers on other forms of fuel will be reduced as the urgency for alternative ways to power our vehicles is put back.
If fracking is only done in low risk ways, there could be a place for it. Push the envelope and the results almost certainly will be very damaging. All we can do is watch with interest.