
You immediately anticipate that this operation can be performed using the recovery function provided by macOS, which consists of downloading the operating system from Internet in "real time" and in its installation on the PC, creating a USB key containing the files. Without this necessary preamble, let's go to the heart of the tutorial and see How to format an iMac (in addition to any another pc of the "bitten apple", the procedure is practically identical). It is not something that always happens, of course, but it can happen and in those circumstances there is no better solution to reinstall the system from scratch. An example of this is when many MacOS updates are performed, that is, more versions of the operating system one on top of the other and the PC stops responding.

However, there are situations where even Apple PCs need a "format".
