OS X El Capitan: About your computer’s firmware

The term firmware refers to computer chips that have data or programs recorded on them. When your computer is manufactured, its firmware is specifically programmed to tell your computer how to perform tasks. However, the type of firmware installed in your computer can be updated later if your computer requires a change.

• Find out if you need a firmware update:
  Firmware updates are provided through the App Store. To check for updates, open App Store and click the Updates button. For