If you’re planning to buy a Surface tablet from Microsoft and you care about the storage space on it then you should be warned. Microsoft has a page on their website that states how many free space you’ll have when you buy a Surface tablet. There are two versions, a 32 GB version and a 64 GB version.
But when you buy the 32 GB version you’ll only get 16 GB of space and when you purchase the 64 GB version there will only be 45 GB of storage space available. While it’s normal for a computer device to have some of the storage taken up by the operating system, on the 32 GB version you lose 50% of the original space, on the 64 GB version you lose 30%.
The space is used, according to Microsoft, for Windows recovery tools (5GB) and Windows RT, Office and built-in apps. You already loose 10% due to the fact that Microsoft advertises the storage space in a decimal system, while the tablet itself uses a binary system which means that 1GB advertised equals to 0.93 GB actual space on the tablet.
Of course on laptops and desktops also some of the freespace is taken up by the operating system and sometimes by pre-installed software. But then it’s usually no more than 5% of the available storage (e.g. 10 GB on a 500 GB HDD).