What is an expansion slot

What is the brown slot near the CPU socket on a Pentium 1 expansion slot definition An expansion card is a printed circuit board that can be inserted into an expansion slot on a computer's motherboard to add new functionality expansion slot types Learn how the Industry Standard Architecture expansion slot allowed upgrades to 8- and 16-bit computers

expansion slot function An expansion card is a printed circuit board that can be inserted into an expansion slot on a computer's motherboard to add new functionality