Adding memory, a disk drive, or other internal component
Many budget-level PCs came with a minimal amount of memory - enough to get by, but not enough to support the increased complexity of today's software. And those hard disks of just a few years ago seem tiny by today's standards. Hardware is cheap! If you have a basic PC that is otherwise in good condition and meets your needs, an upgrade may be a great alternative to buying and setting up a new PC.
Peripherals
Most Peripheral hardware today is designed to interface with the PC via a USB (Universal Serial Bus) connection employing Microsoft "plug and play" technology. Just plug it in and it works! Unfortunately, it's not always that simple making the installation process more like "plug and pray". My PC Therapist knows how to get over those hurdles and will set up your new device and make sure everything works perfectly.