Does anyone know what the difference is between Research assistant, associate and fellow?

Is it possible to do a postdoc fellowship in 6 months?

I have been offered a Research assistant position to start after my phd for 6 months but wondering how this differs from a fellowship?

Thank you.

I am assuming you are talking about UK?

These things can be confusing to a fresh PhD - and to the experienced people as well. These posts are in fact relative and every university seems to have its own system. But in general, if a university offers all these 3 posts, the hierarchy is: Research Assistant --> Research Associate --> Research Fellow. This is the rule of thumb. That is to say, a person who does not hold a PhD yet gets Research Assistant post and a fresh PhD (or one with very little postdoctoral experience) gets Research Associate (so he/she gets quite a bit of supervision from the PI). A postdoc who is experienced/confident enough to carry out research pretty much on his/her own is given Research Fellowship.

Having said this, not all universities have all these 3 positions. There are some university departments in the UK - and pretty good ones at that - which only offer Research Assistant posts in science for postdoctoral work. No Research Associate posts there! On the other hand, there are also some UK universities which give Research Fellow positions straight after completing PhD! No Research Assistant or Associate posts there.

So this must be looked at in relative terms. You must consider what the standing of the given university is. Good universities usually tend not to give away Fellow or even Associate positions easily and an Assistant would be a respectable postdoctoral position there.

It *is* confusing and I think there is a need to bring in some sort of uniformity in this across the country.