Chapter 1 Introduction to Computers and Programming
System software
the programs that control and manage the basic operations of a computer are generally referred to as a system software
Key words or reserved words
the words that make up a high- level programming language
Pixels
tiny dots on a image
Storing characters
any piece of data that is stored in a computer's memory must be stored as a binary number
Bytes
A computer's memory is divided into tiny storage location known as bytes. - one byte is only enough memory to store a letter of the alphabet or a small number
Microprocessors
CPU's are small chips known as microprocessors
Machine language
CPUs only understand instructions that are written in machine language
Software
Programs are commonly referred to as a software. Software is essential to a computer because without it a computer can do nothing
Read only memory (ROM)
a computer can read the contents of ROM, but cannot change its content or store additional data
Syntax error
a mistake such as a misspelled key word, a missing punctuation, character or the incorrect use of an operator
Programmer/ Software Developer
a person with the training and skills necessary to design, create, and test computer programs Work in: business, medicine, government, law enforment, agriculture, academics entertainment and almost every other feild
Interpreter
a program that both translates and executes the instuctions in a high level programming
Compiler
a program that translates high-level language program into a separate machine language program
Program
a set of instructions that a computer follows to perform a task Ex: Microsoft Word, Powerpoint
Syntax
a set of rules that must be strictly followed when writing a program
Code
a statement that a programmer writes in a high-level programming
Binary numbering system
all numeric values are written as sequences of 0's and 1's Ex: 10011101
High level language
allows you to create powerful and complex programs without knowing how the CPU works, and without writing large numbers of low- level instructions
Universal Serial Bus Drives/ USB drives
are small devices that plug into the computers USB port and appear to the system as a disk drive - stored in flash memory
Software developmental tools
are the programs that programmers use to create, modify, and test software
Low level language
because assembly language is so close in nature to machine language it is referred to as low-level language
Digital data
data that is stored in binary and a digital device is any device that works with binary data
Bits (binary digit)
each byte is divided into eight smaller storage location known as bits (known as switches that can be turned off and on) OFF= 0 ON=1
Secondary Storage
is a type of memory that can hold data for long periods of time even when there is no power to the computer
Unicode
is an extensive encoding scheme that is compatible with ASCII, and can also represent the characters of many of the world's language
Output
is any data the computer produces for people or for other devices. Ex: sales report, list of names, graphic images. The data is sent to an output device which formats and presents it
Input
is any data the computers collects from people and from other devices. The components that collects the data and sends it to the computer is called an input device
Operating system
is the most fundamental set of programs on a computer. An operating system controls the internal operations of the computer's hardware, manages all of the devices connected to the computer
Central Processing unit (CPU)
is the part of a computer that actually runs programs (CPU is often referred to as the processor, CPU is the most important component in a computer because without it the computer could not run software - BIG VACUMS
Random access memory (RAM)
main memory is commonly known as random- access memory (RAM) - called this b/c CPU is able to quickly access data stored at any random location in RAM - Volatile type of memory that is used for only temporary storage
Main memory
main memory is the computers work area. This is where the computer stores a program while the program is running, as well as the data that the program is working with
IDE's (integrated development environments
most IDE's combine the following programs into one software package
Two's complement
negative numbers are encoded using the two's complement technique
Utility Program
performs a specialized task that enhances the operation of the computer or safeguards data
Operators
programming language have operators that perform various operations on data
Application software
programs that make a computer useful for everyday tasks are known as application software
Floating- point notation
real numbers are encoded using the floating- point notation technique
Hardware
refers to all of the physical devices, or components that a computer is made of
American Standard Code for Information Interchange (ASCII)
set of 128 numeric codes that represent the English letters, various punctuation marks, and other characters Ex: A= 65
Cloud storage
storage that is stored on a remote server via the Internet or via a companys private network
Solid state drives
store data in solid state memory are more popular b/c the drive does not require any moving parts and operates faster than traditional disk drives
Traditional disk drives
stores data by magnetically encoding it onto a circular disk
Instruction set
the entire set of instructions that a CPU can execute is known as the CPU's instuction set
Statements
the individual instructions that you use to write a program in a high- level programming language are called statements
Digital
used to describe anything that uses binary numbers
Assembler
used to translate an assembly language program to a machine language program
Assembly language
uses short words that are known as mnemonics - mnemonics add numbers, mul typically means to multiply numbers, mov typically means to move value to a location in a memory
Fetch- decode- execute cycle
when a CPU executes the instructions in a program it is engaged in a process that is known as the fetch decode execute cycle 1. Fetch (read) 2. Decode (decodes the instructions) 3. Execute (perform the operation)
Running/ Executing
when a computer is performing the tasks that a program tells it to do we say that the computer is running or executing the program