What is the primary purpose of expansion slots on a motherboard?

The primary purpose of expansion slots on a motherboard is to install adapter cards. These slots provide the necessary connections for additional components, such as graphics cards, sound cards, network cards, or other specialized hardware, allowing users to enhance the capabilities of their computer. By using expansion slots, users can customize their system to meet specific needs or improve overall performance.

This customization is vital in modern computing since it enables the addition of newer technologies without having to replace the entire motherboard or system. Each adapter card inserted into an expansion slot typically comes with its own set of functionalities, which can range from improved graphics to enhanced communication capabilities.