Such expanders offer the advantage of allowing more devices of a particular port type to be utilized at the same time.
Two basic forms of port expander exist: internal and external.
An internal expander has a connection inside the computer, typically on the motherboard, and the only part the user sees is the expansion plate containing multiple ports.
An external device plugs into the existing port and then has multiple places to connect.
Manufacturers have produced expanders for nearly every type of port,[citation needed] but the most common household versions connect to universal serial bus (USB) or to Ethernet ports.