Mods (short for modifications) are anything that changes Minecraft's game content from what it originally was. Mods are getting increasingly popular and in-depth, adding whole new experiences and goals to the game.

Like This!

Purpose of mods

Most mods in Minecraft add content to the game to alter gameplay, change the creative feel or give the player more options in how they interact with the Minecraft world. Most people that mod Minecraft use MCP to do so. Some may be bigger expansions, such as the Aether mod, which adds a significant amount of new content to the game, such as new blocks, mobs, abilities of the player(s), and/or items to create and use. Other mods add more settings and options to optimizing speed, graphics, or gameplay of the game. Others, such as MystCraft and Portal Gun bring another game's features and experiences into Minecraft. Others, are "Toy mods" that bring another less useful but entertaining and playful experience to Minecraft. Server mods or plugins mainly give server admins more options and ease of use, and most mods for single-player have a server version that allows or optimizes the mod in multiplayer.

Ideally, the creator of a mod updates the mod whenever the game updates - bringing more content, bug fixes, or optimizations. Otherwise, the mod may not work with a newer version. Many in the community appreciate the additional experience and ease of use that come with mods, while others play the original game, with only the original content. While Minecraft mods are generally safe to install, one should exercise caution with mods to prevent crashes, deletion of game or save data, system instability, or potential malware infections from a bad link or the mod itself. A good way to protect your game from such problems is to back up various files such as the .minecraft folder if you choose to use mods. There are many mods or plugins available to complement the original game or give server admins more options and control over their servers.

Mods and bugs

If you install a mod, no matter how simple, it may stop the game from working properly. If that happens, there may not be much point reporting bugs on the bug tracker, because Mojang does not undertake to support modified versions of the game. If you encounter a problem while using mods and want to report it, first remove all of your mods and see if the problem still happens. If so, it can be reported on the relevant Issues page here on the Minecraft wiki. Otherwise, try to reproduce the problem with the fewest possible number of mods, and then report the problem to the author(s) of those mods; Mojang won't be able to help.

If Minecraft crashes, a modified game is flagged in the crash report. The following link explains how to obtain a crash report. (Note: If your Minecraft has never crashed, following those instructions won't find anything.)

The crash report text will include a line near the top which will say one of:
Is Modded: Probably not Is Modded: Very likely Is Modded: Definitely {name of custom client}

A shortened example crash report is given below:


'Probably not' appears when the client/server brand appears to the in-game check to be unaltered (often termed 'vanilla') and the meta-inf file is still there. 'Very likely' appears when the meta-inf file is not present but the client/server brand seems to be vanilla. 'Definitely' plus the client name appears when the client is not vanilla. For example, you might see something like:The code that checks for mods is fairly simple, and it's not always correct; it may say 'probably not' even with mods installed. However, it's very difficult to get the 'very likely' message if you haven't modified minecraft.jar somehow, so that's essentially a 'yes'. There's also a 'definitely' message, seen when a Bukkit server crashes and possibly under other similar conditions.
Is Modded: Definitely: Bob's Custom Mod

Official Plugin API

The Plugin API is an upcoming feature that allows modders to easily add more content to the game. For more information, see the above link.

How To Install Mods

The above link provides a comprehensive guide on how to install mods. Some mod packs have auto-installers that make adding mods to Minecraft extremely easy for the beginner modder. If you are an advanced modder you would know that it also involves extracting and adding modified files manually which create a different feel or certain type of gameplay to Minecraft.

Client mods

TIP: Use Ctrl + F (Windows or GNU/Linux) or o Cmd + F (Mac) to find a mod you are looking for, however you must first expand the tables.

Client mods are modifications to your game files themselves. They are not custom clients, and they require modification of minecraft.jar. Like high resolution textures, they only work with the launchers, and won't work if you play through a browser.

The most common form of client mods are aesthetic and/or functional (such as the iMod). However, some client mods add new content to the game (Such as the Supplycrate mod), and others fix issues with the game.

As the Minecraft server software will ignore custom content from client side, most of the client mods which add new content to the game do not work in SMP unless a modification has also been installed on the server. Some authors of client mods have made server versions of their mods available, and others have not. A few of the Loader/API type client mods (e.g. ModLoader and AudioMod) and many of the functional client mods (e.g., Rei's Minimap and TooManyItems) have effect in SMPstraight away, without any modification on server side.