Hey all, i have been reading some c++ books and they talk about a variable type called float but they also mention another one named double and another one named long double but what i don't understand is the difference, the furthest i get is that they tell me float is single precision, double is double precision and long double is extended precision.

But i don't see the difference and whats a precision?

Thank you in advanced.

PS:If you know a book which explains c++ 100%(or more then 70%) for a beginners pleas tell me the name of the book.