Just like in the US, money talks over here, there are several private health providers
basically you pay an insurance premium and should you need any treatment they will sort it out for you. Usually without the wait and using the latest/greatest methods and medicines
though there are plenty cases where the wealthy with medical insurance just get pointed in the direction of the NHS (National health Service) for their treatment
the main advantage of going private is that not all treatments are available on the NHS - elective treatments aren't covered - such as plastic surgery. Though some plastic surgery will be treated - i.e. if you've been in an accident. Some patients will get it if they can convince their doctor that they need it because it is causing them emotional or mental problems.
the other main advantage is that you can get treated much quicker
you get instances of oap's waiting years for a cataract operation or hip replacement. In some cases you won't get a cataract treatment on a single eye, they'll wait until both are affected and do them at the same time - which is damn inconvenient.
i'm sure there are loads of other cases where operations take months/years to get sorted (my partners father has to wait 2 years for treatment on a problem he is having with his ankle - though that is in ireland, not the UK)
my own advice is - if you can afford it, get private coverage - as you really don't want to mess about with your health or wait until something gets so bad you need emergency treatment or it affects your quality of life.
the NHS is great for emergencies but i wouldn't want to trust my overall well being and comfort in their service.
And i don't mind paying for it - i'm in good health now and rarely use it, but there are lots of folk less fortunate than me - and one day, i'll be old and i'll be in the hospital every other week needing some part of me fixed up!!