These Zero Insertion Force (ZIF) sockets clamp onto a chip, making a good electrical connection when you push the lever down. When you release the lever, it releases the chip. This allows you to repeatedly insert or remove a chip from the socket without damage to either.
This socket is designed for DIP chips of up to 40 pins and up to 0.6" wide. So really, it's good for any size chip you'll find. What's nice about it is it can snap into an existing circuit board or socket that is designed for a 40-pin 0.6" chip so you may not have to redesign the board!