“Ok, i don’t exactly understand this my self, but it think they are erased in the same fashion as on a computer. The software writes all zeros to the memory.”
It does work like on a pc, however the data itself isn’t deleted. All that is deleted are some entries in the tables which tell the storage device what files are on the device and where the data is physically stored on the device. That is why often data that has been deleted is recoverable, unless the storage device needed that space for new data, in which case it could have written new data to those locations(since the tables indicate those place are now unused, even though the old data is still there).