Primary Memory (RAM)
Place where all data/programs currently being processed are kept.
Secondary Storage
HDD/SSD/Optical are places where data can be store if power is lost/RAM is volatile.
Processor (Speed)
Does all the calculations in a computer system - speech is a measurement of how many calculations can be done/second.
Bandwidth
Measurment of how much data can be sent at the same time in a certain time frame (also called bitrate). Affects how long it takes before data is processed in its entirety.
Screen Resolution
Measurment of pixels in height x width of computer display.
Sound Processor
Sound reproduction is done by a separate processor - frees up CPU to do other calculations. Can also contain a bank of sampled sounds.
Graphics Processor
Does complex processing - examples include the NVIDIA graphics card. Alleviates pressure of CPU
Cache
Contains the instruction/data that the CPU is likely to request from RAM - makes sure that CPU doesn’t have to wait for instructions
Network Connectivity
Each network card connects to a particular type of network media
Processor Cores
Each processor has at least 1 ALU or core - the more cores, the more tasks a system can perform simultaneously.
Mainframe
Thousands of cores with lots of primary/secondary memory - used with major companies.
Servers/Server Farms
Many high spec PCs running in parallel - used to serve networks.
Multi-programming system
System that can have different programs (apps) installed.i
Single programming system
Can only run one program/set of programs
Multi-user system
Many users on same machine or connected to the same network.
Functions of an OS - Device Configuration
Controls peripheral devices connected to the computer. Through drivers, ‘translation’ programs, etc, controlling devices like keyboards, mouses, etc.
Function of an OS - Files Management
Transfers files between main memory and secondary storage, manages file folders, allocates the secondary storage space, and provides file protections recovery.
Function of an OS - Memory Management
Allocates the use of RAM to requesting processes. To manage primary memory, the OS has to ensure that each process has its own allocated memory space.
Function of an OS - Interface Platform
Allows the computer to run other applications.
Virtual Memory
Feature of an OS that allows compensation of shortages of physical memory by temporarily transferring pages of data from RAM to disk storage.
Folder Structure/Directory Structure
OS manages security access through hierarchical folder organization.
User Interface
Used to interact with the computer to perform various tasks.
Time-slicing
With a multi-user system, a time slice is the set amount of processing time each user again. With a single-user system, a time-slice is the set amount of processing time each program gets.
Interrupt Handling
Function of the OS/device whose execution is triggered by the reception of an interrupt. Generally used to handle high-priority conditions.
Polling
Process where the computer waits for an external device to check for its readiness or state.
Interrupt
Signal to a processor emitted by hardware or software indicating an event that needs immediate attention.
Paging
When using virtual memory, the OS moves other pages to the hard disk so it has room to bring the pages it needs ASAP from temporary disk storage.
Role of Abstractions
Leads to simplicity as users don’t see the hardware directly
Drive Letters
Single alaphebetic character that has been assigned to a physical drive
Java Virtual Machine
Also known as a JVM, it interprets binary code so a processor can perform instructions.