Computer Hardware Components

To control all parts of the computer and send commands to them

Step 1: The CPU has three parts — ALU, Control Unit, and Memory Unit, each with a different role. Step 2: The Control Unit acts like a manager or supervisor. Step 3: It retrieves data and instructions from memory and directs other parts of the computer on what to do. Step 4: It sends commands to all parts including peripherals like printers and keyboards. Step 5: Mathematical calculations are done by the ALU, not the Control Unit. Permanent storage is done by secondary memory, not the Control Unit.

Windows Operating System

Step 1: Software is of two types — System Software and Application Software. Step 2: System Software controls the operations of the computer system and provides a platform for other software to run. Step 3: The Operating System (like Windows, Linux, or Android) is the best example of system software. Step 4: Application software is designed for specific tasks — MS Word is for writing documents, MS Excel is for spreadsheets, and Adobe Photoshop is for editing images. Step 5: These applications run on top of the system software, so the Operating System is the correct answer here.

Convert digital signals to analog signals and vice versa

Step 1: Computers understand only digital signals (represented by 0s and 1s). Step 2: However, communication lines (like telephone lines) often carry analog signals, which are continuous wave-like signals. Step 3: A modem (Modulator-Demodulator) solves this problem. Step 4: It modulates outgoing digital signals from the computer into analog signals for transmission. Step 5: It also demodulates incoming analog signals back into digital signals that the computer can understand. So a modem acts as a translator between digital and analog signals.

Serial Port

Step 1: Communication ports connect peripheral devices to the CPU. Step 2: A Serial Port transmits data serially — that means one bit at a time over a single wire. Step 3: If a byte (8 bits) is to be sent, a serial port takes 8 separate turns to send it, making it slower. Step 4: Serial ports are available with 9 or 24 pins and connect devices like mouse and modem. Step 5: A Parallel Port sends 8 bits at once (much faster), and a USB Port uses a single plug arrangement without pin configuration. So Serial Port is the correct answer.