Computer Science 1.1

Central processing unit (CPU)

Critical component that carries out the majority of the processing inside a device. (made up of CU and ALU)

Control Unit (CU)

Directs the operations of the processor. Responsible for the fetch-decode-execute cycle.

Arithmetic Logic Unit (ALU)

responsible for performing arithmetic and logic operations.

Register

very small amounts of storage that are available directly on the CPU to hold temporary data that the CPU may be working on.

Instruction register (IR)

instruction is fetched from memory, it is held in ________

Program counter (PC)

Holds the address of the next instruction that is to be fetched from memory.

Memory address register (MAR)

Holds the memory address that is currently being fetched.

Memory data register (MDR)

Holds the data that has been fetched or is about to be written.

Accumulator (AC)

Stores the intermediate arithmetic or logical results produced by the ALU.

Buses

Critical component of the computer system,. Transfers data between various devices.

Control Bus

Used to transmit command and control signals from the CPU to other components of the system.

Data bus

carries the data being processed between the peripherals

Address bus

used to transmit the address that is to be read from or written to in memory

Bidirectional bus

a bus that can transfer data in both directions

Cores

configurations of CPUs

SIngle-core processors

a single processing unit, it can only handle one task at a time.

Multi-core processors

Can run multiple instructions simultaneously.

Co-processors

has a specific job to support the main CPU.

Graphics processing unit (GPU)

a specialized electronic circuit designed ot accelerate the rendering of visuals.

Shaders and textures

techniques used in 3D rendering to apply effects

Parallel processing

the ability of the GPU to perform many calculations simultaneously

Matrix and vector multiplications

fundamental operations in machine learning and graphics that involve complex math calculations.

Deep learning

a subset of machine learning that uses an artificial neural network to imitate the define of the human brain.

Proof of work

a consensus mechanism requiring cryptominers to solve complex problems.

random access memory (RAM)

holds instructions and data for programs that are currently running. (Volatile)

read-only memory (ROM)

used for storing instructions that are very rarely modified (not volatile)

L1 cache

located directly on the CPU, making it the fastest type of cache. It can be accessed instantly

L2 cache

can either be on the CPU or situated very close to the CPU. 256KB - 2MB per core.

L3 cache

is often located the furthest from the CPU chip.

The fetch-decode-execute cylce

fundamental process that a CPU uses to execute instructions.

Little man computer

easier way to see these stages carried out in more detail.

Multi-core architectures

systems with multiple CPU cores on a single chip, allowing parallel execution of instructions and tasks.

Basic pipeline

consists of multiple stages or segments situated between an inut end and an input for the next.

Independent execution

each core in a multi-core processor has its own set of pipelines.

Parallel execution

allowing multiple cores to work on different parts of a single large tasks or multiple tasks simultaneously

hard disk drive (HDD)

storage, older technology but are still often used, especially in non-mobile devices. suitable for storing large volumes of data.

Solid state drive (SSD)

have no moving parts. They sue flash memory to store data, offering high-speed data access and durability.

Embedded MultiMediaCard (eMMC)

in low cost devices, such as entry-level smartphones and budget laptops. Type of flash storage that utilizes NAND flash memory

Memory Cards

compact storage devices often used in cameras, smartphones and other portable devices.

Network Attached Storage (NAS)

Dedicated file storage connected to a network that allows multiple users to access data.

Lossless compression

data is compressed to a smaller size, but can be restored back to the original without any loss of information.

Lossy compression

Stronger than its counterpart, however it reduces filed by permanently eliminating certain information. This is information that is redundant or less critical.

Run-length encoding (RLE)

effective lossless data-compression technique used to reduce the size of files containing many consecutive repeated characters.

Transform coding

form of lossy compression often used in JPEG image compression or MP3 audio compression

forward transform

carried out in each of the sub-images. The forward transform can use different algorithms, depending on the type of file compression.

High-frequency data

correspond to rapid changes in pixel values, representing fine details, edges and textures.

Low-frequency data

correspond to slow changes in pixel values, such as broad areas.

Software as a Solution (SaaS)

delivers software applications over the internet,. Users can access these application through web browsers without needing to install, maintain or update the software locally.

Quantizer

reduces file size by simplifying the frequency coefficients obtained from the DCT

Symbol encoder

quantized coefficients are further compressed using entropy coding techniques.

Platform as a service (PaaS)

Provides a cloud-based platform that allows developers to build, test and deploy applications without managing the underlying infrastructure.

Infrastructure as a Service (IaaS)

Provides virtualized computing resources over the internet, such as virtual machines, storage and networks.