Remember in high school how cool regular things looked though a microscope? Well, macro photography is basically the same. Cool as hell.
Macro photography is, put simply, taking pictures of things really close up. When taking these close shots a good amount of magnification is usually involved.
While it is not required to have a special lens to pull of a macro shot; you really should. A kit lens will just not be able to capture the fine details that are present in a macro. So while you may get a shot that looks alright, it won’t be great.
A cheap option is to use lens extension attachments. This will allow a regular lens to focus on the very small objects. While it will not be optimal, it is a very good option.
Even cheaper is a filter specifically designed for close up focusing. Though the image quality will still be nothing compared to a dedicated lens.
A dedicated macro lens is going to be your best bet. The long barrel and advanced focusing mechanisms will allow for the best possible shots. If used correctly, that is.
The only issue with macro lenses is that the photographer must be fairly close to the subject. In fact, some lenses are able to focus while touching the subject. This means that lighting will be a huge obstacle. Some photographers add flash rings to the end of the lens, while others use flash bulbs set to the side. All of these will work, as well as many other methods of lighting.