Yes if you save passwords, cookies etc. in general. IE you store everything on your PC. Not a good secure way of using the 'net. If , on the otherhand, you delete cookies, passwords etc when you shutdown, for security reasons, then Ccleaner is excellent. Download it and read the help files.
Microsoft Lumia 950 vs Lumia 950 XL: What's the difference between Lumia 950 & 950 XL?