What is the name of StarCraft's 1998 expansion pack?

StarCraft's 1998 expansion pack is titled StarCraft: Brood War.

Brood War was developed by Blizzard Entertainment and released for Windows and Macintosh. It adds new campaign chapters, units, tilesets, music, and multiplayer balance changes to the original game. The expansion continues the conflict after the events of StarCraft and follows the consequences of the Zerg and Protoss wars.

The expansion is sometimes confused with two earlier licensed add-ons, Insurrection and Retribution, which were created by third-party developers. Brood War is the official Blizzard expansion and became especially important to the game's professional competitive scene. It also introduced units such as the Protoss Dark Archon, the Terran Medic, and the Zerg Lurker.