A monitor works as an output device by displaying visual information on its screen. It receives signals from the computer's graphics card or integrated graphics, interprets the data, and then shows the image or video on the screen, allowing you to see the output of your computer.

A computer keyboard is an input device used to enter characters and functions into the computer system by pressing buttons, or keys. It is the primary device used to enter text. A keyboard typically contains keys for individual letters, numbers and special characters, as well as keys for specific functions.

They are used to move the cursor on the screen, select objects and click on buttons. The mouse, which individuals use to direct cursors and make selections on a computer screen, is integral to graphical user interfaces.

A hard disk drive (HDD) is an internal or external computer component that stores data, such as the operating system, applications, and user files.  Internal hard drives are installed inside the computer's case and are directly connected to the motherboard and power supply. 

The CPU interprets, processes and executes instructions, most often from the hardware and software programs running on the device. The CPU performs arithmetic, logic, and other operations to transform data input into more usable information output.

A motherboard is the main circuit board in a computer system. It connects all of the internal components, like the memory, processor, graphics card and other hardware. It also provides power to each component and allows them to communicate with each other.

Memory is the electronic holding place for the instructions and data a computer needs to reach quickly. It's where information is stored for immediate use. Memory is one of the basic functions of a computer, because without it, a computer would not be able to function properly.