BEC 4 - IT Flashcards
What are the 5 components of a computerized system?
- hardware
- software
- networks
- people
- data
List the 3 categories of hardware.
- Processor
- Storage
- Peripherals
What is a CPU
Central Processing Unit - control center of the computer
What are the 2 principal components of a CPU?
- Processor
2. Primary Storage
What does a processor do?
- interprets program instructions
- coordinates input, output and storage devices (the control unit)
- performs arithmetic calculations (arithmetic logic unit)
What does primary storage do?
- “main memory”
- used to store program instructions and data until the program instructions can be executed
What are the 2 categories of primary storage for personal computers?
- Random access memory (RAM) - stores data temporarily while it is being processed
- Read-only memory (ROM) - used to permanently store data needed to power the computer
What is virtual memory?
- NOT real memory
- temporary “storage” of portions of programs that are not being used
- retrieved and brought into actual physical memory when neede
What are secondary storage devices? List examples.
- means to permanently store programs and data
- hard drives, magnetic disks, flash drives, CD-ROM discs, optical discs, magnetic tape
What are the 2 types of secondary storage devices? Which type is faster?
- Random storage devices - data is accessed randomly
- sequential storage devices (i.e. tape) - data accessed sequentially
Sequential storage devices are faster
What type of storage is used for disk storage?
RAID (Redundant Array of Independent Disks)
- combines multiple inexpensive disk drives into an array of disk drives to obtain performance, capacity and reliability that exceed that of a single large disk drive
- can be implemented in hardware and software
- hardware implementation provides better performance
What is a peripheral? What are the 2 types?
devices that transfer data to/from the CPU but do not take part in actual processing of the data
- Input Devices - supply data to be processed
- i.e. keyboards, mice, scanners, magnetic ink character readers (MICR), though sensitive screens, microphones - Output Devices - transfer data from the processing unit to various output media
- i.e. printers, speakers, cathode ray tubes (monitors), plotters (graphics printers)
Note: hardware devices can act as both types
List the 5 classes of processors
- Mainframes - include specialed processors to handle certain specialized functions like input, output, telecommunications (which are relatively slow)
- Midrange
- Minicomputers
- Personal computers
- Supercomputers - used for specialized processing
How is processing power measured?
MIPS (millions of instructions per second)
Note: speed of input and output devices can affect processing power
What is multiprocessing? What are the 2 types of multiprocessing?
Multiprocessing - coordinated processing of programs by more than one processor
- Symmetric Multiprocessing - one operating systems controls the processing
- Parallel processing - each processor has its own operating system; simultaneous use of more than one computer to execute a program which first has to be divided into parts that can be executed separately
