Central Processing Unit (CPU) | Arithmetic Logic Unit (ALU) |
Control Unit (CU) | Registers |
Program Counter (PC) | Instruction Register (IR) |
Memory Data Register (MDR) | Memory Address Register (MAR) |
The part of the CPU that performs arithmetic and logical operations. | The part of a computer that performs most of the processing of data and instructions. |
Small, high-speed storage locations within the CPU that hold data and instructions for processing. | The part of the CPU that manages the flow of data and instructions within the CPU. |
A register that holds the current instruction being executed. | A register that contains the memory address of the next instruction to be executed. |
A register that holds the memory address of data being transferred to or from memory. | A register that holds data being transferred to or from memory. |
Accumulator | Fetch-Decode-Execute Cycle |
Clock Speed | Cache Memory |
Machine instruction cycle | Fetch-decode-execute cycle |
Processor | Program counter |
The process by which the CPU retrieves, interprets, and executes instructions. | A register that holds the result of arithmetic and logical operations performed by the ALU. |
A small amount of high-speed memory located within or near the CPU that is used to temporarily store frequently accessed data and instructions. | The rate at which the CPU's clock generates pulses that synchronize the operations of the CPU. |
The process by which a computer retrieves an instruction from memory, decodes it, and executes it. | The process by which a computer retrieves a program instruction from memory, interprets it, and executes it. |
A register in a computer's processor that holds the address of the next instruction to be executed. | A part of a computer that carries out instructions and performs arithmetic and logical operations. |
Instruction register | Opcode |
Operand | Addressing mode |
Control unit | Execution cycle |
Memory | Registers |
A code that identifies a specific operation to be performed by a computer's processor. | A register in a computer's processor that holds the instruction currently being executed. |
A method used by a computer's processor to identify the location of data in memory. | A value on which an operation is performed by a computer's processor. |
The phase in the machine instruction cycle where the processor executes the instruction. | A part of a computer that manages the flow of data within the computer and controls the execution of instructions. |
Small, high-speed storage locations within a computer's processor that hold data and instructions temporarily during processing. | A device that stores data and instructions for a computer to use. |
Cache memory | Cache hit |
Cache miss | Cache line |
Level 1 (L1) cache | Level 2 (L2) cache |
Level 3 (L3) cache | Write-through cache |
When the CPU requests data that is already stored in the cache. | A high-speed component of a computer's memory hierarchy designed to store frequently accessed data for rapid access. |
The smallest unit of data that can be cached. | When the CPU requests data that is not in the cache. |
A larger cache that is slower than L1 cache, but still faster than main memory. | The cache closest to the CPU, typically smaller but faster than higher levels of cache. |
A type of cache that immediately writes any changes to both the cache and main memory. | A cache that is even larger and slower than L2 cache, typically found on multi-core processors or in server systems. |
Write-back cache | Cache coherence |
Temporal locality | Spatial locality |
Primary Memory | Random Access Memory (RAM) |
Read-Only Memory (ROM) | Volatile Memory |
The process of ensuring that all caches in a multi-processor system have a consistent view of the system memory. | A type of cache that does not immediately write changes to main memory, but instead waits until the cache line is replaced or the system is shut down. |
The tendency of computer programs to access data that is located close to other recently accessed data. | The tendency of computer programs to access data that was recently accessed. |
A type of primary memory in which any location can be easily accessed in a random manner, and data can be written or read from any memory location independently of other locations. | The main memory of a computer that stores data and instructions for immediate use by the CPU. This memory can be both volatile and non-volatile. |
Memory that requires a constant supply of power to retain its contents. RAM is an example of volatile memory. | A type of primary memory that contains data that cannot be modified or deleted. It is used to store system software such as BIOS. |
Non-Volatile Memory | Memory Address |
Memory Access Time | Cache Memory |
Memory Hierarchy | Memory Controller |
Memory Module | Memory Bank |
A unique identifier that is assigned to each memory location in the primary memory. | Memory that retains its contents even when power is turned off. ROM is an example of non-volatile memory. |
A small amount of high-speed memory used to temporarily store frequently accessed data or instructions for faster access. | The time taken by the primary memory to read or write data from or to a memory location. |
The circuitry in a computer system that controls the flow of data between the CPU and the memory. | An arrangement of storage devices in a computer in which each type of storage is used for a different purpose and has a different access speed and capacity. |
A group of memory modules that work together to provide a larger memory capacity for the computer. | A small circuit board that contains several memory chips used to expand the memory capacity of a computer. |
Persistent Storage | Volatile Storage |
Non-Volatile Storage | Hard Disk Drive |
Solid-State Drive | USB Flash Drive |
SD Card | Cloud Storage |
Refers to temporary storage of data on a computer system. The data is lost when the power to the system is turned off. | Refers to long-term storage of data on a computer system. The data remains even after the power to the system is turned off. |
A non-volatile storage device that stores data permanently on magnetic disks. | Refers to long-term storage of data on a computer system. The data remains even after the power to the system is turned off. |
A non-volatile storage device that uses flash memory to store data temporarily or permanently. | A non-volatile storage device that stores data permanently on memory chips. |
A non-volatile storage service provided by companies like Google, Amazon and Microsoft that allows users to store and access data over the internet. | A non-volatile storage device used in cameras, phones, and other mobile devices. |
Magnetic Tape | RAID |
Backup | Archive |
Operating System | Kernel |
Memory Management | Multitasking |
A storage technology that uses multiple disks to provide data redundancy and improve performance. | A non-volatile storage medium used for backup or archiving data. |
A process of storing historical data that is not frequently accessed to free up space on the primary storage. | A process of copying and archiving data to prevent data loss from hardware failure, human error or natural disasters. |
The kernel is a central component of most computer operating systems; it is the core part of the OS that manages input/output requests from software, translates them into data-processing instructions for the central processing unit and interfaces with the computer's memory and peripheral devices. | An operating system (OS) is a collection of software that manages computer hardware resources and provides common services for computer programs. |
Multitasking is the ability of an operating system to run multiple programs or processes at the same time. | Memory management is the function of an OS that allocates and de-allocates available space in computer memory, and may also include tasks such as moving data between memory locations to optimize usage. |
Device Drivers | Shell |
File Management | Security |
Virtual Memory | Batch Processing |
Real-time Processing | Multiprocessing |
A shell is a user interface for accessing an operating system's services and commands. It provides a command-line interface (CLI) or graphical user interface (GUI) for interacting with the operating system. | Device drivers are software components that enable communication and control of hardware devices by the operating system. |
The security function of an operating system is to protect the computer system and its data from unauthorized access, modification, or destruction. | File management is the process by which an operating system organizes and manipulates files and directories (folders) of data on a computer storage device. |
Batch processing is a technique used by operating systems to execute large batches of computer tasks automatically, without manual intervention. Tasks are usually initiated by a user command or scheduled using system tools. | Virtual memory is a technique used by an operating system to allow a computer to compensate for shortages of physical memory by temporarily transferring pages of data from random access memory (RAM) to disk storage. |
Multiprocessing is the ability of an operating system to use multiple computer processors or cores to perform tasks more efficiently and improve overall system performance. | Real-time processing is a technique used by operating systems to process data as it comes in, without waiting for a batch process to finish. It is typically used for time-sensitive applications such as process control or simulation. |
Application | Common Features |
User Interface | Input Validation |
Security | Data Storage |
Error Handling | Compatibility |
The interface elements and functionalities that are shared across different applications. | A software program designed to perform a specific task or set of tasks. |
The process of checking user input to ensure that it is safe and appropriate for the application's intended use. | The visual elements and controls that allow a user to interact with an application. |
The manner in which an application stores and retrieves information from a database or other data store. | The measures put in place to protect the integrity, confidentiality, and availability of an application's data and resources. |
The ability of an application to function correctly across different hardware and software platforms. | The methods used by an application to respond and recover from errors and exceptions. |
Localization | Accessibility |
Scalability | Usability |
Application software | Operating system |
Word processor | Spreadsheet application |
The design of an application to enable people with disabilities to use it successfully. | The adaptation of an application to fit the language and cultural preferences of its users in different regions. |
The ease with which an application can be learned and used by its intended audience. | The ability of an application to accommodate a growing number of users, data, or processing demands. |
The software that manages the hardware and software resources of a computer system. | Computer software designed to perform a group of coordinated functions, tasks, or activities for the benefit of the user. |
An application software used for organizing, analyzing, and manipulating numerical data. | An application software used for creating, editing, and formatting text documents. |
Presentation software | Project management software |
Database management system | Web browsers |
Email clients | Media player |
Graphics software | Antivirus software |
An application software used for planning, organizing, and managing resources to complete specific tasks or projects. | An application software used for creating visual presentations with a set of slides. |
The software used to access the World Wide Web, including browsing web pages and downloading files. | An application software used for managing and organizing data in a database system. |
An application software used for playing audio and video files. | An application software used for managing email accounts, sending and receiving messages, and organizing emails. |
An application software used for preventing, detecting, and removing malicious software such as viruses, spyware, and adware from a computer system. | An application software used for creating, editing, and manipulating digital images or graphics. |
Bit | Byte |
Binary | Denary/Decimal |
Hexadecimal | Conversion |
Binary to Denary/Decimal | Denary/Decimal to Binary |
A group of eight bits that represents a single unit of data. | A binary digit that can be either 0 or 1. |
A numbering system that uses ten digits (0-9) to represent numbers. | A numbering system that uses only the digits 0 and 1 to represent numbers. |
The process of changing a number from one numbering system to another. | A numbering system that uses sixteen digits (0-9 and A-F) to represent numbers. |
The process of converting a denary/decimal number to a binary number. | The process of converting a binary number to a denary/decimal number. |
Binary to Hexadecimal | Hexadecimal to Binary |
Radix | Positional Notation |
Data Representation | Binary representation |
ASCII | Unicode |
The process of converting a hexadecimal number to a binary number. | The process of converting a binary number to a hexadecimal number. |
A system of representing numbers where the value of a digit is determined by its position in the number. | The base of a numbering system. Binary has a radix of 2, denary/decimal has a radix of 10, and hexadecimal has a radix of 16. |
A way of representing data using only two digits, usually 0 and 1. | The method used to represent data in a computer system. |
A universal character encoding standard that can represent any character from any language in the world. | A standard code used to represent characters as binary numbers. |
Hexadecimal | Octal |
Byte | Bit |
Analog data | Digital data |
Metadata | Checksum |
A base-8 number system that uses eight distinct symbols to represent numbers. | A base-16 number system that uses sixteen distinct symbols to represent numbers. |
The smallest unit of data in a computer system, representing either a 0 or a 1. | A unit of data that consists of eight bits. |
Data that is represented using a finite set of discrete values, usually 0 and 1. | Data that is continuous and can have any value within a range. |
A value used to verify the integrity of a data transmission, by calculating the sum of the transmitted data. | Data that describes other data, providing information about its content, quality, condition, etc. |
AND | OR |
NOT | NAND |
NOR | XOR |
Boolean operator | Logical operator |
A Boolean operator that returns true if at least one of the operands is true. | A Boolean operator that returns true if both operands are true. |
A Boolean operator that returns false if both operands are true, and true otherwise. | A Boolean operator that reverses the logical state of its operand. |
A Boolean operator that returns true if the operands have different values, and false otherwise. | A Boolean operator that returns false if at least one of the operands is true, and true otherwise. |
A type of operator that performs logical operations on two or more Boolean expressions. | A type of operator that operates on Boolean values. The result of a Boolean operation is either true or false. |
Binary operator | Unary operator |
Operand | Truth table |
Truth table | Logical operator |
AND | OR |
A type of operator that operates on a single operand. | A type of operator that operates on two operands. |
A table used to represent the relationship between the inputs and the outputs of a logical circuit or a Boolean function. | A value on which an operator operates. |
A symbol or word used to connect two or more expressions, producing a compound proposition. Common logical operators include AND, OR, NOT, and XOR. | A table used in logic to determine the truth value of a compound proposition. It lists all possible combinations of truth values for the propositions in the compound proposition and the resulting truth value of the compound proposition. |
A logical operator that returns true if at least one of its operands is true. | A logical operator that returns true only if both of its operands are true. |
NOT | XOR |
Compound proposition | Propositional variable |
Truth value | Open sentence |
Atomic proposition | Tautology |
A logical operator that returns true if its operands have opposite truth values. | A logical operator that returns the opposite of the truth value of its operand. |
A symbol or letter used to represent a proposition in a logical expression. | A proposition that is formed by combining two or more propositions using logical operators. |
A propositional expression that contains a variable or variables instead of specific values. | The value assigned to a proposition to indicate whether it is true or false. |
A compound proposition that is always true, regardless of the truth values of its constituent propositions. | A proposition that cannot be further subdivided into simpler propositions. |
AND gate | OR gate |
NOT gate | NAND gate |
NOR gate | XOR gate |
Truth table | Logic expression |
A logic gate that performs the OR operation on two or more inputs, producing a high output if at least one input is high. | A logic gate that performs the AND operation on two or more inputs, producing a high output only if all inputs are high. |
A logic gate that performs the NAND operation on two or more inputs, producing a low output only if all inputs are high. | A logic gate that performs the NOT operation on a single input, inverting the input to produce the opposite output. |
A logic gate that performs the XOR operation on two inputs, producing a high output if the inputs are different and a low output if the inputs are the same. | A logic gate that performs the NOR operation on two or more inputs, producing a low output if at least one input is high. |
A mathematical formula used to represent the logical operation of a circuit, using Boolean operators such as AND, OR, NOT, and XOR. | A table used to represent the inputs and outputs of a logic circuit, showing all possible combinations of input values and the corresponding output value. |
Logic diagram | Gate combination |
Boolean algebra | Digital circuit |
The arrangement of two or more logic gates to perform a specific logical function, such as AND, OR, or NOT. | A graphical representation of a logic circuit, showing the logic gates and how they are connected to produce the desired output. |
An electronic circuit that uses digital signals to perform logical operations, such as those used in computers and other digital devices. | A mathematical system used to represent logical operations, using two values: true (1) and false (0). |