A bit (short for 'binary digit') is the absolute smallest and most basic unit of data in computing. It can represent only one of two states, typically denoted as 0 or 1. All other data units are composed of multiple bits. For instance, a nibble is 4 bits, a byte is 8 bits, and a word can vary in size (e.g., 16, 32, or 64 bits) depending on the computer's architecture, but it is always a collection of bits.

In computing, data storage units often follow a binary progression where each larger unit is 1024 times the size of the previous one. A Petabyte (PB) is a very large unit of digital information storage. Following this standard, 1 Petabyte (PB) is equivalent to 1024 Terabytes (TB). To further illustrate: 1 Terabyte (TB) = 1024 Gigabytes (GB), 1 Gigabyte (GB) = 1024 Megabytes (MB), and 1 Megabyte (MB) = 1024 Kilobytes (KB).

Computer forensics investigates digital evidence for legal and criminal cases.

Computer-based examinations (CBEs) offer several advantages over traditional paper-and-pencil tests. A significant benefit, and often a primary reason for their adoption, is the ability to automate the scoring process. This automation allows for instant results and immediate feedback to be provided to the test-taker, which can be highly beneficial for learning and understanding performance. Option A is incorrect because CBEs are often administered in dedicated computer labs or with provided devices, not necessarily requiring each student to own a personal computer. Option C is incorrect; like any technology, CBEs are susceptible to technical glitches, though robust systems aim to minimize them. Option D is incorrect as CBEs inherently require electrical power to operate computers and servers.

An analog computer represents data using continuously variable physical quantities, such as voltage, pressure, or, in the case of a slide rule, physical lengths. The slide rule operates by aligning scales to perform mathematical operations like multiplication and division based on logarithmic scales, where distances represent numerical values. In contrast, modern electronic calculators, smartphones, and desktop PCs are all examples of digital computers, which represent data discretely using binary digits (0s and 1s).

Computer-Based Testing (CBT) refers to a modern assessment methodology where candidates use a computer to take an exam. This involves questions being displayed on a screen and responses being entered digitally, rather than on paper. Key characteristics of CBT include electronic recording of responses, often automated scoring, and the potential for a wide variety of interactive question types (e.g., drag-and-drop, simulations). This method enhances efficiency, security, and provides immediate or faster feedback compared to traditional paper-based exams. Option A describes traditional paper-based testing. Option C describes an oral exam. Option D is incorrect as CBT inherently involves electronic devices.

A Personal Computer (PC) is explicitly designed for individual use, offering a balance of performance, cost, and functionality tailored for tasks such as word processing, internet browsing, gaming, and personal media management. In contrast, 'Supercomputers' are high-performance machines used for complex computational problems, 'Network Servers' manage resources and provide services to multiple clients over a network, and 'Mainframe Systems' are powerful computers used by large organizations for critical applications requiring high reliability and performance, serving many users simultaneously. The very name 'personal computer' directly indicates its intended single-user purpose.

Versatility is the characteristic that enables a computer to perform a wide array of diverse tasks, ranging from basic calculations and word processing to complex scientific research, intricate simulations, and multimedia creation. This ability stems from its programmable nature, allowing it to load and execute different software applications designed for specific purposes. Unlike a calculator, which is designed for arithmetic, a versatile computer can function as a calculator, a word processor, a gaming console, a communication device, and much more, adapting its functionality based on the software it runs. Speed refers to how quickly it performs tasks, accuracy to its precision, and diligence to its ability to perform repetitive tasks without errors or fatigue.

The term 'hertz' (Hz) is the standard unit of frequency, representing one cycle per second. In computing, it is primarily used to measure the clock speed of a Central Processing Unit (CPU). A higher hertz value (e.g., gigahertz, GHz) indicates a faster clock speed, meaning the CPU can execute more processing cycles and instructions per second, leading to quicker overall performance. Option A refers to storage capacity, typically measured in bytes (e.g., gigabytes, terabytes). Option C refers to data transfer rate, commonly measured in bits or bytes per second (e.g., megabits per second, Mbps; gigabytes per second, GB/s). Option D refers to screen resolution, measured in pixels (e.g., 1920x1080 pixels).

In computing, memory and storage capacities are typically measured using a binary-based system (powers of 2). While 'giga' generally implies 10^9 (1,000,000,000) in the metric system, in the context of computer storage, a kilobyte (KB) is 1024 bytes, a megabyte (MB) is 1024 kilobytes, and consequently, a gigabyte (GB) is 1024 megabytes. This convention stems from the binary nature of computers, where 2^10 = 1024 is the closest power of two to 1000. Therefore, 1 Gigabyte is equivalent to 1024 Megabytes.