Fanzines are home-made magazines. I made my first one in High School with my friend Paul. I'm going to sound like a dinosaur but we typeset the first issue on a mechanical typewriter. We had it photocopied at school and then posted copies to our readers.
When we launched Thunderwind we marked it as issue zero. The thinking being, that by issue one it might look professional. It didn't. We sold some copies though, so we went all in and bought a word processor for our BBC Micro. Each issue was an improvement on the last and by the end we'd even grown a team of contributors.
I later contributed comics and artwork to Black Mole and From the Sublime. The last fanzine I contributed to was Tales of the Reaching Moon . They published their final issue in 2000 and after that most fandom went online.