Windows 8 / Windows 7 / Windows Vista / Windows XP
McEdit is easily the most popular Minecraft world editor out there. It serves to help players quickly create highly complex custom worlds, move players around, do some landscaping, and in general complete tasks that would have taken hours or even days to complete in Creative mode.
McEdit allows players to open saved Minecraft maps and fly around making desired changes without affecting any other aspects of their game. Using the in game character, McEdit gives players the ability to select areas to edit, delete, copy, or paste new blocks. McEdit also comes with a "paintbrush" that creates large swathes of the player's chosen material wherever they paint. The paintbrush is also customizable in size, so mapmakers can add fine details or paint mountains and lakes in a single stroke. In addition to the paintbrush, there are fill and replace, clone, and filter tools. Players can also use McEdit to change the map's spawn point.
Actually using McEdit can be somewhat difficult. Editing in 3D can be very confusing, especially when characters are very close to the area being edited. Fortunately, McEdit has thorough explanations for all of its tools, making it a good editor for novice mapmakers. Functions in McEdit are easy to pick up, so new users will be pros by the end of their first session. Plus, McEdit adds a measure of usability to Minecraft itself. With McEdit, players can mine on a massive scale, create paths down from high ledges, move their spawn point near their house, and even create adventure maps for other players to enjoy.
One complaint about McEdit is that the graphics don't always match up to the item selected, such as decorative grasses and torches. However, the interface in general is lauded by the majority of users for its simplicity and straightforward presentation.