(1)Old Minecraft Versions

Servers that run on older Minecraft versions (like Beta, 1.2.5, 1.7.10, 1.8, etc.) to keep the mechanics, combat, worldgen, and quirks from that era. They usually lock the server to that version or use plugins to support old clients, and tend to attract players who want pre-1.9 combat, classic survival, or period-specific minigames.