This is just another term for patches, and is pretty much used interchangably. So these are fixes for parts of code which are found to have vulnerabilities in them, and are generally released on a regular basis by software vendors.
An Uninterruptable Power Supply (UPS) is basically just a large battery which allows a device to stay powered up until it can be safely / properly switched off. It allows you to close any open / running software and reduces the risk of corrupting files.
Many data centres will have banks of these as well as generators to ensure that file servers can be shut down, and to maintain a service if there are fluctuations in the power supply.
Universal Serial Bus (USB) is the name given to the type of connection which is now popular for connecting external devices to computers. Most of us think of memory sticks / pen drives, but many things like external hard drives, keyboards and mice also use USB connectors.
As part of any login process, you need to have a unique identifier, something that tells the computer you are the person trying to gain access. This is your username (or login / logon name) and is almost always used with a password or some form of Two Factor Authentication.