When getting into Minecraft modding, you first need to understand the difference between a Minecraft Mod and a Minecraft Plugin. Don't worry... you're not the only one who is unsure (that's exactly why we've written this article!).

If you don't fancy reading too much, here's a summary in just a few words...

Minecraft mods change the fundamental game, such as adding an entirely new animal or in-game item. A mod needs to be installed on your computer and your server.

Minecraft plugins add extra functionality into the game, such as the ability to set warps or homes. A plugin can only be installed on your server.

Before we go into more detail, let's first understand the relationship between a Minecraft Client and a Minecraft Server:

  • A Minecraft Client is the Minecraft software which is installed onto your computer. We call this client side.
  • A Minecraft Server runs independently to your Minecraft Client. We call this server side.

Minecraft Plugins are installed on the Minecraft Server and not on the Minecraft Client. This is called server side because all the changes are made on the server rather than the Minecraft Client. This allows anyone to connect to your server and use the plugins which you installed by just using the default Minecraft Client. This is the preferred method for server owners because it makes managing your server far easier.

Minecraft Mods generally speaking, are designed to be run on your Minecraft Client. If you install a mod onto your Minecraft Client and want to connect to a Minecraft Server then it's important that the Minecraft Server also has the exact same mod installed. If the server doesn't have the same mod installed then the mod won't work.

To add confusion... there are exceptions.

Some mods will only work on your Minecraft Client and some will only work on your Minecraft Server - just like how a plugin would work. If you try to install a client side only mod onto your server then the server won't start. Likewise, if you try to install a server side mod onto your computer then your Minecraft Client won't start.

If you want to run a Minecraft Server with mods, then you must tell the players connecting that they also need to have the mods installed onto their Minecraft Client. If they don't have the mods, then the server will automatically disconnect them. Let's take this example... let's say you try and install a mod onto your Minecraft Server but not onto your Minecraft Client. When you try and connect to your Minecraft Server, the server will automatically disconnect you with a message similar to the screenshot below.

Mod Rejections through Forge

In a perfect world, mods would be cross compatible so you would only ever need to install them server side. The real problem lies in the fact that you can't modify textures or game mechanics server side. You can only change the fundamental game through a client side modification.

Happy mining! ⛏️