Although there are many differences between the two, the thing that truly sets PlayStation apart from Microsoft are the exclusives.
Whilst Microsoft likes to focus on making their console as powerful as possible (as evidenced by the Xbox One X), PlayStation tends to focus on their massive library of exclusive franchises to make investing in their system more worthwhile.
It's certainly worked, especially in 2017.
As it stands, PlayStation may be starting to rival even Nintendo for the wealth of franchises and characters they have under their belt. The huge amount of games in exclusive franchises coming from Sony in any given year is exactly what makes it exciting to be a Sony fan. Combining this with fantastic third party support, and it's looking like a pretty great generation for PlayStation.
Unfortunately, games like The Last of Us, Until Dawn and Horizon: Zero Dawn won't be making it onto the list because they currently only have one entry in their respective franchises. They certainly deserve to be included, but let's hope Sony flesh them out in due course.
For now though, let us know your own favourite PlayStation franchises down in the comments below.