The end result of that is that if you're using an SSD and it fails, the chances of any data recovery software retrieving that data is slim to none. A sobering thought.
Choosing the right data recovery software for Mac
The annoying thing about data recovery software is that you only really use it if you have been caught without a backup. The developers have you at their mercy, and if you have lost precious data they could charge whatever they can get away with. But it is a highly competitive market too so the pricing structure has evolved at a sort of equilibrium. Pretty much all data recovery software costs $99 or the UK £ equivalent of that.
The good news though, is that developers don't want to you spend the $99 to then comeback and complain that it didn't work. Thus a vast majority offer a free version that will scan your disk and see what is salvageable. You can then decide of the fragments of your dead drive are worth $99 to retrieve.
All work in a similar way. If the directory telling where files were originally stored is saveable, the rest is easy. But if that isn't the case, the software will scan the data for familiar patterns that would denote a file type. Once they find as file type, there's a good change that the following data will be the file. Highly fragmented hard drives might mean not all files can be retrieved, but given enough time, most will get there in the end.
It can be a time consuming process to piece the bits of files back together. But with patience, most files that haven't been overwritten should in theory be saveable. If a hard drive is still spinning, and the head is still scanning, there is still hope. Sickly drives can take days to fully scan, and the higher capacity they are, the longer it will take. But if it's your wedding photos, or perhaps your Bitcoin vault that is missing, you can afford to wait.
If you don't need data recovery right now, then do yourself a huge favour and make sure your backup strategy is up and running and fool proof. A little pain now will save you a world of hurt in the future. If you have already lost some data, then the process outlined here will help. But without wishing to pour salt in the wound, now would be a really good time to take a look at your back-up strategy.
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