Intro to Computer Systems Flashcards
Moore’s Law
The number of transistors incorporated into a CPU chip will double every 24 months
giga
billion
mega
million
According to Mrs. Anderson what is the most important invention in the 20th century
transistors
CPU
the brains of the computer system
Cache
Memory where instructions and information waiting for processing after they arrive in the CPU from RAM
RAM
stands for Random Access Memory
works with the CPU
is temporary or volatile storage because everything in most types of RAM is lost as soon as the CPU is turned off (computer turned off) or there is a disruption of some sort in the electrical current going to the CPU
System Board
also called the motherboard
controls communication for the entire computer system
the processing speed of microprocessors
the number of times the CPU can fetch and process data or instructions in a second
Cycles of the CPU include
retrieving, decoding and executing instructions and returning the results to RAM
Speed of the CPU is measured
in Hz (Hertz)- CPU cycles per second
megahertz (MHz)- the number of millions of CPU cycles per second
Gigahertz (GHz)- the number of billions of CPU cycles per second
So 1000 MHz = 1GHz
Terahertz (THz)- the number of trillions of CPU per second
ROM
Read-only Memory
ROM chips are not volatile and cannot be changed by the user
contains special instructions for detailed computer operations
Flash Memory
can be updated to store new information like RAM
does not lose the information when power to the computer
Buslines (BUS)
Electrical pathwayw which connect the different compontents
a 64 bit bus can move twice as much info at the same time as a 32 bit bus
Ports
a socket for external devices to connect to the system unit
VGA
Video Graphics Adapter
DVI
Digital Video Interface
USB
connects keyboards, mice, printers,storage devices, etc.
Firewire
connects firewire devices
Ethernet
high speed networking port
Microphone & Headphone
ports
Storage Bays
Hard drive, optical drives, Media card readers, solid state drives
Qwerty
invented to slow people down
Input and output good things to know
details, compare with different sellers, price matching
pointing devices
mouse, track ball, touch pads, pointing stick
multi-touch screens
I-pad, smart phones, tablets
OCR
Optical-character recognition
will actually reproduce it into a text file
output
presents processed data or info in a useable format
Monitor (display screen)
presents visual images of text and graphics
soft copy
monitor (display screen)
hard copy
paper or print
monitor refresh rate
how often a display image is updated or refreshed
about 60 times per second
dpi
dots per inch
printers
inkjet-spray ink
laser- laser light to produce images (more $ upfront but less over time)
Internet telephones
transmission over the internet
requires high speed internet and special software/hardware
Bit
the smallest data element in an electronic system
Primary storage
remember RAM is referred to as primary storage which is temporary or volatile
Secondary Storage
provides permanent or nonvolatile storage
data retained after computer shut off
accomplished by saving to and accessing
slower access speeds than primary storage
not directly accessed by CPU
less expensive than primary storage
Hard discs
inside system unit
when formatted tracks, sectors and cylinders are assigned
magnetic charge on metal disk
stores and retrieves large quantities of info quickly
used to store programs and data files
Optical discs
uses reflected light
flat areas represent 1s and pits represent 0s
CD/DVD/Bluray
Solid state drives (SSDs)
found inside the PC contains solid state memory instead of magnetic disks to store data faster and more durable than hard disks more expensive nothing moveable
Database organization
- character (byte) single letter, number, character, symbol
- Field group of related characters. smallest piece of meaningful data
- Record logical grouping of fields. Entity a distinct item in a database
- Tables
- Databases collection of records or data
software used to create databases
MS Access, MS SQL Server, Oracle 11g, IBM DB2, MySQL
Relational Database
relates or connects data in different tables through the use of a key field or common data element
most likely the type of database to be working with
Key Field
each record in a database has at least one distinct field called the key field (also called the primary key)
A field (column) within a table whose value uniquely identifies an entity, is unique for each record
example: social security number, student ID
tables are related or connected by other tables by a common key field enabling info stored in one table to be linked to info in another
Query
search/ asks questions of a database in its language
What are some of the Boolean operators
and, or, not, near
keyword search
uses keywords to help find specific info stored on a database
quick search
allows simultaneous searching of multiple e-resources-files and URLs
uncontrolled database
the internet
