Lesson overview
The IPOS cycle in a computer system
Computer systems follow a basic cycle known as IPOS, which stands for Input, Process, Output, and Storage. Every task a computer performs passes through these stages. At each stage, different hardware components work together to receive data, transform it, present results, and keep information for future use.
Input devices
Input devices allow users to send data or commands into the computer. Examples include the keyboard, mouse, touchscreen, scanner, microphone, and camera. These devices convert physical actions such as typing, clicking, touching, or speaking into digital signals that the computer can understand.
Without input devices, the computer would not know what the user wants it to do. In practical terms, every activity starts with some kind of input, such as entering a password, clicking a button, or scanning a barcode at a store.
Processing components
After the data is collected, the system moves to the processing stage. This is handled mainly by the Central Processing Unit (CPU), often called the brain of the computer. The CPU performs calculations, follows instructions, and coordinates how data moves around the system.
Other important parts support the CPU. The motherboard connects all the components. The system bus and chipset help data travel quickly between the CPU, memory, and other devices. Random Access Memory (RAM) holds active data and programs while they are being used, which makes processing much faster than reading from long term storage.
Output devices
Once processing is done, the computer needs a way to show the result. This is the role of output devices. Common examples are monitors, speakers, printers, and projectors. A monitor displays text, images, and video. Speakers output sound for music, notifications, or voice calls. Printers create physical copies of documents and images.
Output devices allow the computer to communicate its work back to the user. Without them, the processing would happen silently with no visible result.
Storage devices
The final stage in the IPOS cycle is storage. Storage devices keep data so that it can be used again later. Examples include hard disk drives (HDD), solid state drives (SSD), USB flash drives, memory cards, and external hard drives.
Storage can be permanent or temporary. Permanent storage keeps files even when the computer is turned off, which is why your documents and applications are still there when you restart your device. Temporary storage such as RAM is cleared when the computer shuts down. Both types are important for a smooth user experience.
Putting it all together
The IPOS model shows that a computer is not just a single box. It is a system of input devices, processing components, output devices, and storage solutions that work together.
Input → Process → Output → Storage → Ready for the next task