A computer is a combination of hardware and software.
All computers--from the simple calculator to the complex supercomputer--use a combination of hardware and software. Depending on the functionality of the computer, your hardware and software will vary. Just as there are many types of hardware, there are many types of software available.
Hardware Simplified
Basically, hardware is the physical component that can be touched, be it a digital watch, calculator, cellular phone, laptop, desktop computer or any other item that can hold intangible information. According to Merriam-Webster online dictionary, hardware is defined as "major items of equipment or their components used for a particular purpose" including "the physical components (as electronic and electrical devices) of a vehicle (as a spacecraft) or an apparatus (as a computer)."
Specific Computer Hardware
When you break down a household computer to its hardware elements, computers have similar parts. Each of these affect the whole computer and will increase or decrease performance based on the capability of each part. One piece of hardware often will bottle-neck the system, slowing down how quickly information can be processed. The main components are the motherboard (main component that everything plugs into); the CPU (central processing unit, processes information supplied by the software); RAM (random access memory, temporary storage of software for quick and easy access by the CPU); the hard drive (stores all permanent and some temporary information); DVD/CD-RW/ROM drive (allows a user to read from various disk formats using the ROM "read only memory" or the ability to write and/or rewrite information if the drive is RW "re-writable" or R "recordable"); video card (takes code from software and sends it to the monitor, making it viewable); sound card (takes code from the software and sends it to the speakers, making it audible); keyboard (input device allowing you to enter