Like many other businesses I use Windows 10 and right about now your PC should be nudging you to upgrade with the latest update. When you do agree to update, then expect that the download will take at least one hour, so just let that start in the background. During the actual update you may want to go to lunch, or plan to do this at the end of the business day so that you don't lose any time during working hours.
Microsoft has an official list of the changes here. On the Start menu the columns go from three to four, and you can resize the tiles. You can now cram up to 2,048 items in the Start menu, which is way too many for my taste. Microsoft will now start to suggest apps for you.
Find My Device is useful if your laptop has gone missing, look in Control Panel, then Security.
Boot times could be up to 30% faster now with this update.
Some people have found that their installation gets stuck at 44%, especially if you have an SD card inserted.
Other users found out that default app choices got reset with this update.
There are reports that several programs may be removed during install, like: CPU-Z, speccy, 8gadgetpack, a Cisco VPN client, SATA drivers, SpyBot, F5 VPN, Steam, Origin and Adobe CS, ugh.