Minecraft Forge (1.21.5, 1.21.4) is a modding API (Application Programming Interface), which makes it easier to create mods, and also make sure mods are compatible with each other. It is the foundation of the majority of current mods of Minecraft. Developers can customise Mincecraft based on it. With Minecraft Forge, Minecraft is limitless. To do this, the staff of Forge have always updated versions to make mods compatiable with the update of Minecraft.
Source: Minecraft Forge (1.21.5, 1.21.4)
Check Out: Minecraft Mods
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