Chapter One: Introduction to Computers and Programming Flashcards
Program
set of instructions that a computer follows to perform a task. Commonly referred to as Software.
Programmer
person who can design, create, and test computer programs.
Also known as Software Developer
Hardware
the physics devices or components that make up a computer.
Computer is a system composed of several components that all work together.
Central Processing Unit (CPU)
the part of the computer that actually runs programs.
Most important Component.
Without it, cannot run software.
Used to be a huge device
Microprocessors
CPUs located on small chips
Micro-Memory
where computers store:
A program while the program is running
Data used by the program
Known as Random Access Memory or RAM
CPU is able to quickly access data in RAM
Volatile memory used for temporary storage
Contents are erased when computer is off
Secondary Storage
can hold data for long periods of time.
Programs normally stored here and located to main memory when needed.
Disk Drive
magnetically encodes data on a circular disk
flash memory
portable, no physical disk
optical devices
data encoded optically
Input
data the computer collects from people and other devices
Input devices
component that collects the data
Example: keyboard, mouse, scanner, camera
Disk Drives can be considered input devices because they load programs into the main memory.
output
data produced by the computer for other people or devices
Can be text, images, audio, or bit stream
Output Devices
formats and presents output
Example: video display, printer
Disk Drives and CD recorders can be considered output devices because data is sent to be saved.
software
everything the computer does is controlled by software
Application Software
programs that make computer useful for everyday tasks
Byte
just enough memory to store letter or smaller number
Divided into 8 Bits
Bit (Binary Digit)
electrical component that can hold positive or negative charge, like on/off switch
BINARY NUMBER SYSTEM
8 bits= 1 byte, 1 byte= character, number, or special char
digital
describes any device that stores data as binary numbers
digital images
are composed of pixels
To store images, each pixel is converted to a binary number representing the pixels color
digital music
is composed of sections called samples
to store music, each sample is converted to a binary number
fetch
read the instruction from memory into CPU
decode
CPU decodes fetched instructions to determine which operation to perform
execute
perform the operation
FPU- floating point unit
ALU- arithmetic logic unit
CONT- everything else
what is a program?
the set of instructions that a computer follows to perform a task. commonly referred to as software
what are the 5 major components of a computer system?
CPU microprocessors micro-memory secondary storage Input Output Software
what fundamental set of programs control the internal operations of the computers software?
Operations Software
how much memory is enough to store a letter of the alphabet or a smaller number?
1 byte= 8 bits
on what numbering system are all numeric values written as sequences of 0s and 1s?
computer numbering system
what encoding scheme is extensive enough to represent the characters of many of the languages of the world?
unicode
assembly language
uses short words (mnemonics) for instructions instead of binary numbers.
Easier for programmers to work with
assembler
translates assembly language to machine language for execution by CPU
low-level language
close in nature to machine language.
Example: assembly language
high-level language
allows simple creation if powerful and complex programs
No need to know how CPU works or write large numbers of instructions
a more intuitive to understand
key words
predefined words used to write program in high-level language
Each key word has a specific meaning
operators
perform operations on data
example:agh operators to perform arithmetic
syntax
set of rules to be followed when writing program
statement
individual instructions used in high-level language
compiler
translates high-level language program into separate machine language program.
machine language program can be executed at any time
interpreter
translates and executes instructions in high-level language program.
Used by python language
interprets one instruction at a time
no deprecate machine language program
source code
statements written by programmer
syntax error
prevents code from being translated
