#Minecraft modding is super confusing. Here's a mini-FAQ on all the different modding tools, mostly for my own reference:
Bukkit (aka CraftBukkit): One of the first Minecraft modding tools. Server-side only. Some weird DMCA junk means it's complicated to download.
Spigot: a souped-up Bukkit.
Sponge: Similar in goals to Bukkit, but different and newer. No DMCA junk.
Forge: A different approach to modding than Bukkit. Much more invasive. Optionally includes client-side modding capabilities.
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