MCreator is software for modding Minecraft without programming knowledge (mod generator). It's very simple to use, and its concept is easy to learn. With MCreator, you can make your own mod as you wish. Making new blocks, items, achievements, new types of existing blocks, mobs, biomes, foods, tools, plants, machines (and more!) is possible with MCreator. You've probably never seen a mod maker with so many features. After creating a new mod, you can share it with MCreator's community so other users can use your mod, comment, give you ideas or join with work on your modding project.
NOTE: MCreator is a very active project and has a lot of support but on its website: mcreator.net. This forum thread is not actively maintained anymore.