Timely - data must be efficient and must be provided in a timely manner
Thorough - the data must be complete
Accurate - data should be captured only once, where possible and should be captured
as close to the point of activity as possible.
Reliable - data should reflect stable and consistent data collection processes across
collections points and over time
IPOS - The Input-Procession-Output-Storage Cycle
Input - Raw data is entered by the user.
Processing - Raw data is organized or structured for usefulness.
Output - Information is output so user can see results.
Storage - Processed information is stored for permanent record.
Computer System - A collection of components that work together to meet the needs of
the user; typically categorized as either hardware, software, networks, or users.
Hardware - Physical components of a computer system which include the system unit
and its components and peripheral devices; tangible aspects of the computer.
Software - Computer programs that tell the computer what to do--how to execute
commands and process information
Network - A collection of computers and resources connected by various media so that
they can communicate with each other.
User - Those who use a computer.
Software Categories - Systems Software and Applications Software
Evolution of Users - First users were the engineers who built and programmed
computers, then employees who had received specialized training were users, and now
today, anyone and everyone can be a user.
Protocol - Rules provided by which networks communicate with each other.
TCP/IP - Transmission Control Protocol/Internet Protocol. Most commonly used
protocol; is required of all computers that communicate over the Internet.
,Protocol Stack - A collection of protocols. TCP/IP is an example.
Components of a Computer - CPU, Memory and Storage, Peripheral Devices
CPU - Executes programs' instructions and commands various components in the
computer. Referred to as the "chip".
Memory - Stores the programs being executed and the data they are using.
I/O Subsystem - All peripheral devices where long term storage devices are used.
Bus - Permits information to move between each component; electrical channels that
enable communication among the electronic components
System Unit - Critical component of all computer based systems; consists of most of the
hardware the computer needs in order to run; comes in a variety of shapes and sizes.
Internal Components of the System Unit - Case, Internal Bays, Buses, Ports, Hard
Drive, Motherboard, CPU, CPU Cooler, Memory Module (RAM), Power Supply Unit
(PSU), Expansion Slots/Cards
Parts of the CPU - Control Unit (CU) - retrieves the instructions and the raw data that is
input and coordinates or controls the sending of those instructions and data to the ALU
Arithmetic Logic Unit (ALU) - does the actual processing of the data; completing
mathematical calculations and logical operations to process the data and converting the
input of the keyboard text entry to output displayed on the screen
System Clock - Controls the speed at which instructions are processed.
RAM - Stands for Random Access Memory.
It temporarily stores data before it is processed and sent to your screen or printer.
It is volatile (means data or information stored disappears when the computer is turned
off or loses power).
You can choose the amount of RAM your computer has.
Types of RAM - Dynamic RAM (DRAM) - typically called main memory
Static RAM (SRAM) - cache memory and registers
BIOS ROM - BIOS stands for Basic Input Output System; ROM stands for Read Only
Memory.
, Typically stored in ROM chip on the motherboard.
Is software not hardware, ("basic" operating system that runs when the computer is first
turned on).
Runs tests of memory and the CPU and initializes hardware components so that the
actual Operating System can be loaded from the hard disk.
Can't choose the amount or contents.
1st Generation of Computers - Vacuum tubes, relay switches, the need to program in
machine language
2nd Generation of Computers - Transistor components, magnetic core memory, smaller
size, easier to program, disk drives and drums, called mainframe computers
3rd Generation of Computers - Silicon chips (known as ICs - integrated circuits),
reduced cost, called mini computers, networks introduced via dumb terminals
4th Generation of Computers - Single chip processor, called microcomputer, first
personal computer, rudimentary computer graphics, home use
Moore's Law - Doubling of transistor count roughly every 18 - 24 months (exponential
increase)
Evolution of Storage - Punch cards, magnetic tape, hard disks, floppy disks, optical
discs, flash memory, cloud storage
Machine/Low-level Language - Written for a specific machine by the engineers who built
and ran the computers; no need for OS since only one program could run at a time
Assembly Language - Easier than machine but still required detailed, precise low level
instructions
Language Translator Programs - Function is to translate one program language into
another; take source code and convert it to another form; source code by itself cannot
be read by a computer
Compiler - Improve language translator; requires that the components of the software all
be defined before compilation can begin; code is more effcient
Structured Programming - Programmer is limited to high level control constructs such as
while loops, for loops, and if/else statements and not allowed to use primitive GOTO
statements