CCS64 is a Commodore64 emulator for Windows, Some of the emulated things are:
The main Commodore 64 console, with the keyboard and peripherals like joysticks, paddles and mouse. It emulates both the different systems sold in Europe as well as the USA.
Up to four 1541 disk-drives are emulated (which means that you use special files on your PC, as a replacement for the old 5 1/4 inch floppy disks).
The C2N cassette recorder is also emulated (which means the you use special files on your PC, as a replacement for the old magnetic tapes).
Many of the old cartridges (that means special hardware expansions for the C64, which were plugged in at the back of the computer) are also emulated.