Cravings are intense - sometimes overwhelming - urges or compulsions, which have their roots in both our physiology and our psychology.
Alcohol does some ferocious things to your basic neurological survival mechanisms.
Alcohol - and other addictive drugs - can hijack chemical reward loops in our brains, so that the search for and consumption of alcohol becomes as important as eating, sleeping, keeping warm and just staying alive. This helps to explain just how people can carry on drinking despite the carnage and chaos that they create around them when they do.
We all learn various behaviours that seem to become almost automatic. Once you've learnt to drive, for example, you'll always be susceptible to banging your foot on the imaginary brake pedal if you're a passenger.
Similarly, you'll probably have learnt to associate starting to drink with particular events and situations:
These associations become particularly powerful when you've found that drinking gives you either pleasure, or relief from physical or mental distress.
Of course these 'positive' effects are only ever short lived - alcohol never really gave anyone lasting pleasure or relief. But psychologically, we know that the associations you learn from short-term reactions - whatever the longer term consequences - are particularly strong.
Read more about coping with cravings here