According to this chart, you won't lose much via the Windows 8.1 upgrade process; however, there may be many that can better address your concern as I have not done the upgrade myself because I opted to do an clean install of 8.1.
However, based on the number of issues still being identified and researched, I would definitely recommend that you wait a bit, unless you are just too curious to do so. Good luck with your own decision.
If I upgrade to windows 8.1, will I lose all of my installed programmes.
Is windows 8.1 worth installing, is it better than windows 8
Are you already using Windows 8? If so, did the computer come with Win 8 or did you install? How old is your computer?
As my2cents said, there are many pitfalls with updating to 8.1, not the least of which is the age of your computer. As a f'r instance, my older self-built 64 bit system ran Windows 8 Pro 64 bit just fine, but when I attempted to install 8.1 64 bit, I couldn't. I was able to install Windows 8/8.1 32 bit just fine, though. Go figure.
Brink (Shawn) has created a nice file that gives instructions on Microsoft's Upgrade Assistant, which will tell you if your system complies:
At any rate, if everything's a go, you won't lose any of your installed programs or files; however, remember! BACKUP, BACKUP, BACKUP! your system before you start anything. That way, if things go south, you'll come out on the other end alive.
Computer Type PC/Desktop System Manufacturer/Model Number HP Pavilion 500-056 OS Windows 8.1 CPU AMD Elite Quad-Core A8-6500 Memory 8 GB Graphics Card AMD Radeon HD 8570D Monitor(s) Displays Acer 23" Screen Resolution 1920 X 1080
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