Answer:
The terms used in HD television are confusing and inconsistent.
The one term that is consistent is "HD ready". It means that if the television receives an HD signal, it will display it. However, it has nothing to do with the resolution of the screen itself. There have been HD ready televisions marketed that had a screen resolution of 480 lines which is the resolution of standard definition in North America. Whatever HD signal that television received, the end result can never be any better than standard definition. Such marketing is misleading and dishonest.
"Full HD" normally indicates that the television has a native resolution of 1920 x 1080. This is the highest HD standard being broadcast today and such a television is capable of retaining the full quality of the incoming signal. However, the term is sometimes used to describe other features of the television. The only way to guarantee that the television is full HD resolution is to examine the specification. If the spec says that the screen resolution is 1920 x 1080, it's full HD. If the spec says it can display a 1920 x 1080 signal, this does not mean the screen itself is that resolution.
Despite the numbers, the best way to select a television is to look at it. If the image looks good, the detailed specification is not important. It is important to do the research before going to the shops. Having information will help to survive the misleading and uninformed salesmen that are found in so many stores. By no means all salesmen are of this standard - many are honest, competent and informed. Your job is to know enough to tell them apart.