About your Mac notebook computer’s power adapter
If you have a Mac notebook computer, plugging in the power adapter provides power to the computer and recharges the computer’s battery. For optimal performance, use the power adapter that came with your Mac notebook computer—either a MagSafe or USB-C—or a compatible replacement adapter. See the Apple Support article Find the right power adapter and cable for your Mac notebook.
You can purchase a compatible replacement adapter from apple.com or an Apple Store.
About MagSafe power adapter light colors
When you first connect a MagSafe power adapter to a compatible computer, the adapter light glows green for about a second to indicate that power is available. After that, the adapter light glows green or amber.
Green: A steady green light indicates that the battery is fully charged.
Amber: A steady amber light indicates that the battery is being charged.
To learn more about your computer’s battery, see Manage your Mac notebook computer’s battery.