You have multiple options when it comes to getting closer in your images. Here is a brief run down of the ways to it, with visual references for how close you can get. (All images shot from the closest focusing point. Canon products were used for these examples.)
Items you can use:
* a macro lens (for close up)
* a long zoom lens for far away shots (not macro)
* an extension tube
* a lens converter
* a close-up lens or filter
A lens converter or teleconverter contains glass elements and increases the entire focusing range. These are better for distance as opposed to macro.
A close-up lens, close-up filter, or macro filter are all basically a simple secondary lens. They contain piece(s) of glass and screw into the filter threads on the front of you camera lens. They enable macro photography by allowing your lens to focus more closely. These work similar to a pair of reading glasses.