Paper, Fabric, Forge and Vanilla explained

When you make a server you pick its software. Here is what each one is for, in plain terms.

The options

• Vanilla is the plain game exactly as Mojang ships it. No mods, no plugins. Best if you just want the normal experience.
• Paper is Vanilla plus plugins and big performance improvements. This is the most popular choice for survival and SMP servers. Plugins are server side, so players join with a normal unmodified game.
• Fabric is a lightweight mod loader. Players need the same mods installed to join. Great for performance mods and lighter modpacks.
• Forge is the heavyweight mod loader behind most big modpacks. Also requires players to have the mods.
• Purpur is Paper with extra tweaks and settings, if you want even more control.

Plugins or mods?

• Want to add features without players installing anything? Use Paper and plugins.
• Want to change the game itself with mods, or run a modpack? Use Fabric or Forge, and everyone joins with the matching mods.

You can change your mind later, see How to switch server software.