Firmware
Occasionally, changes and improvements to the system software (firmware) on the micro:bit are needed. Updates to the firmware are made by the micro:bit Education Foundation.
Do I need an update?
Changes to the firmware don’t happen very often. You probably don’t need to update it for your micro:bit if everything is working alright. Sometimes there’s a problem with a certain part of the board not working right or it has trouble connecting to your computer or other device. In those cases, a firmware update may include a fix for the problem.
Getting a firmware update
Instructions for updating the firmware are shown on the firmware upgrade support page at microbit.org.