It's a simple question, but one that everyone ponders from time to time: how does that computer in front of you actually work? Computers have evolved from simple devices to a 21st-century staple in just a few decades. But despite being a relatively new technology, most people have no idea how a simple rectangle—small enough to fit your backpack—is capable of everything from complex math to playing video, audi lo, and running sophisticated software. So, how does a computer work, and what components do you need to make one?
- What Is a Computer?
A computer is a programmable electronic device capable of processing information. Composed of hardware and software, computers operate on two levels: they receive data through an input route, either live or through a digital storage unit, and send out an output.
Modern computers shouldn't be mixed up with the outdated job occupation of computers in the 19th century. While they both perform long and tedious mathematical calculations and information processing, one is a person, and the other is a machine.
- How Does a Computer Work?
A computer processes the input to produce the desired output, but how does a machine outperform the human brain?
Conventional computers don't try to mimic the human brain. Instead, they run commands sequentially, with data constantly moving from input and memory to the device's processor. Neuromorphic computers, on the other hand, process data at the same time, making them faster, energy-efficient, and closer to the structure of the human brain.
Overall, a computer works in four steps:
Input: Input is the data before processing. It comes from the mouse, keyboard, microphone, and other external sensors.
Storage: The storage is how the computer retains input data. The hard drive is used for long-term and mass data storage while the data set for immediate processing is stored temporarily in the Random Access Memory (RAM).
Processing: Processing is where input gets transformed into output. The computer's Central Processing Unit (CPU) is its brain. It's responsible for executing instructions and performing mathematical operations on the input data.
Output: Output is the final result of data processing. It can be anything from images, video, or audio content, even the words you type using a keyboard. You can also receive the output through a printer or a projector instead of directly through your device.
All this play a vital role in the working of a computer system.
- Hardware and Software
The input and output devices that can be physically touched are known as Hardware of the system. Such as keyboard, mouse, screen, etc. The applications that reside in the Computer and can only see them but cannot touch them are known as Software. Such as Microsoft Word, Excel, Paint, and all the installed software on the system.
- How does it all make a computer to work.
These major components of a computer system together enable a computer to work.
- Operating System.
The system's booting process begins that load the operating system (Windows, Linux, Mac, etc.) with all associated files. The bootstrap loader starts the booting of the system. So, in this way, Windows and its other essential services get loaded to the system.
As the operating system has been loaded to the Computer, the installed Hardware of the systems becomes active and able to communicate with the CPU. The communication of the hardware devices is performed via an interrupt request (IRQ). When the current task is already in execution, the interrupt controller sends the request to CPU to stop processing a new hardware request until the execution of the current task gets completed. The CPU keeps the new request on hold, and that process is stored as a memory address in the memory stack. When the current task execution is finished, the task on hold is resumed and processed. However, if the Computer fails in the POST test, an irregular POST is encountered. We can understand the irregular POST when we hear a beep coming from the system that notifies us that some problem has occurred.
When we switch on the computer system by pressing the power button, a signal reaches the power supply that converts the alternate current into the direct current, also known as DC. After that, a .proper ample power is supplied to each component of the Computer.
With no issues, all components come in their active state, the power supply sen,ds a signal to the motherboard and CPU via transistors. During the time, the processor removes the leftover data in the memory, and the CPU becomes ready to take over the instruction (input) and process it.
A POST (power-on self-test) is performed on the Computer in a sequence to ensure that the major computer components exist and work properly. When the Computer passes the test, firstly, the 64-bytes memory wakes because it carries the system time and date information and all other hardware-related information installed on the system. This information starts loading and POST checks and compares this information with the system settings. If compared successfully, it loads the basic drivers (that allows communication of hardware devices with CPU and Computer to continue to boot) and interrupts handlers for the installed Hardware such as a keyboard, hard drive, mouse, and many more.
After that, POST checks the display adapter, and with no issues found, it loads the display that we see on the computer monitor. Next, it is checked that whether Cold boot or reboot (warm boot) is performed by looking at the memory address 0000:0472. If it is 1234h, it means it is a reboot, and the rest of the POST steps are skipped. But, if it not so, it means it is a cold boot, and the remaining POST steps are continued. Now, the RAM installed on the computer system is checked.
At last, POST tests the optical drive and hard drive of the Computer by sending signals to them. When all drives successfully pass the test, the POST is finished and instructs to begin the loading of the Computer Specifications or Specs describes the hardware specifications of a computer system. It describes the capabilities, features, and components of a computer system. It means it describes the CPU speed, RAM storage, model, and other system components. The computer specs are determined and checked usually when we have decided to purchase a new computer system or laptop, or we are a gamer. If we are already aware that what specifications are good, we will always have a fruitful deal of purchasing a new computer system.