Test: Computer Hardware - 1 - SSC CGL MCQ

The primary function of an input device in a computer system is to input information into the computer. Input devices like keyboards, mice, touchscreens, and scanners allow users to provide data and instructions to the computer. This data is essential for analysis, storage, and commanding the computer on what actions to take.

A keyboard controller in a computer system is responsible for converting the data from pressed keys on the keyboard into computer language. When a key is pressed, the keyboard controller stores the code of the key in the keyboard buffer, which is then processed by the computer. This conversion allows users to input text and commands effectively.

A significant feature of various types of keyboards is that they have different layouts. Keyboards like QWERTY, DVORAK, and AZERTY have distinct key arrangements, designed to cater to different language needs and typing preferences. These layouts offer users options based on their comfort and efficiency in typing.

Function keys, labeled F1 to F12 on a keyboard, can be programmed for specific actions, such as opening help menus, saving files, or executing commands in software applications. These keys provide shortcuts for various functions, enhancing user efficiency and productivity.

The Backspace key is used to erase or delete the character to the left of the cursor on a keyboard. It allows users to correct typing errors efficiently by removing characters in the reverse direction of typing. This key is essential for editing text and ensuring accuracy in written content.

The Num Lock key is used to enable or disable the numeric keypad on a keyboard. When activated, the Num Lock key allows users to input numbers and perform calculations using the dedicated number keys on the right side of the keyboard. Disabling Num Lock transforms these keys into additional navigation and editing functions.

The primary function of a mouse as a pointing device is to enable the input of data and commands in graphical form by moving a pointer on a monitor. This allows users to interact with a computer system by positioning the cursor on the screen, moving objects by dragging, and selecting objects by clicking.

Trackballs are commonly used in CAD/CAM workstations. These workstations often require precise control and movement of the cursor, making trackballs a suitable pointing device for such applications.

Unlike a mouse, a joystick enables movement in every direction covering a full 360 degrees. This feature allows for more versatile control and is particularly useful in applications such as flight simulators and CAD/CAM systems where precise and multidirectional movement is required.

OMR stands for Optical Mark Reader. This technology is widely used to identify marked responses on paper using light reflection, allowing for data translation for storage, analysis, and reporting. It is commonly utilized in reading objective test answers, voting systems, and evaluations.

The primary purpose of OCR, or Optical Character Recognition, is to scan printed pages and convert them into editable text. This technology is essential for computers to understand image content by transforming dots into readable letters and words. It is commonly applied in extracting text from images, such as reading utility bills or insurance documents.

OMR translates marked answers into computer-processable data through light reflection. By detecting marks on paper using light, the system notes the presence or absence of data, which is then decoded into patterns for computer processing. This method enables efficient data extraction for various applications like reading objective test answers and evaluations.

Input devices contribute to the functioning of a computer system by providing data and instructions to the computer. These devices enable users to interact with the computer by inputting information that is crucial for analysis, storage, and commanding the computer on various tasks.

The Escape key, also labeled as Esc, is used to cancel ongoing operations, close dialog boxes, or exit full-screen mode in applications. Additionally, pressing Ctrl along with the Escape key can open the Start menu on Windows systems. This key provides a convenient way to interrupt actions or navigate software interfaces quickly.

The primary function of a light pen is to move and control the cursor on a computer screen. This handheld electro-optical pointing device is used for tasks such as making drawings, graphics, and menu selections by detecting light from the screen when brought close, allowing for precise interaction with the displayed content.