Socket Sets can be incredibly versatile, particularly if you regularly have to tighten and loosen nuts and bolts. A typical Socket Set will include pieces in a range of sizes, so you can tackle nuts and bolts of different sizes but the individual pieces will usually all be the same drive size.
The drive size might be ½ inch, ¼ inch or 3/8 of an inch, this last size being adaptable to ¼ and ½ inch sockets for a variety of uses.
Socket Sets often come with a range of handy extras to help you get more done, such as handles, bits and screwdrivers. Plus, in most cases, the set will be supplied in a handy carry case, helping you to keep everything tidy and organised.