Windows 2000 dropped on February 17, 2000, and it was basically Microsoft’s way of telling everyone, “Hey, Windows 98 was cool, but we’re growing up now.” Built off the Windows NT backbone, it was way more stable and way less crash-happy than anything before it. It came in four versions — Professional, Server, Advanced Server, and Datacenter Server — depending on how serious you were about your setup. Windows 2000 brought in big upgrades like Active Directory, better Plug and Play support (finally), and way tighter security (for the time). Service Pack 1 hit later in 2000, SP2 in 2001, SP3 in 2002, and SP4 in 2003 — each update hammering out bugs and boosting performance. If you were running a real business (or just hated rebooting five times a day), Windows 2000 was the move. Solid, dependable, and honestly way ahead of its time.