Expansion Card
A plug-in hardware module that extended a computer's capabilities by adding sound, graphics, networking, or memory through a standardized bus slot.
Before everything moved onto the motherboard, you added features with expansion cards: a Gravis UltraSound for better audio, a 3DLabs card for 3D graphics, extra RAM, or a network adapter. Each card had its own quirks and capabilities. Demo groups would scour the market for the newest, fastest hardware — a 3DLabs Prophet gave you a real advantage in the mid-1990s. Writing a demo that ran well on multiple cards was an achievement; most teams optimized for whatever they could get their hands on.