51 terms

AP Java Ch. 1

Central Processing Unit (CPU):
The CPU is the component that executes programs and carries out instructions. Everything you see on your computer screen at any given time is being processed by your CPU.
Graphical User Interface
The Graphical User Interface (GUI - "gooey") allows the user to interact with the programs, to the user, the GUI is the program. GUI is the user interface for most modern operating systems and applications* and uses graphical screen elements
divide the screen into separate work paces
Machine Language
most basic type. Each type of CPU has its own language so something written for Windows 7 can't run on Mac OS X. Machine language is binary and so code isn't easy to read or write.
Assembly Language
next level up, replaces binary digits with mnemonics (short English-type words representing commands or data). Because it is not in binary, this takes slightly longer to run than machine language.
High-level Languages
most programmers use this to write software by using English-like phrases. 1 high-level programming statement can accomplish the equivalent of many machine language instructions. Java is a high-level language, as is C, C++, Ada, and Smalltalk.
translates code from one language to another, the original is known as source code, the translated, is know as the target language. Most compilers translate the code only once and normally is translated directly into machine language.
are like compilers but the interpreter does the translation and execution in short bursts. A small part of source code is translated and executed, then another. This technique eliminates the need for a separate compilation phase but it runs more slowly because the translation process occurs during each execution of code
information is continuous (alcohol thermometer, the alcohol rises in the tube the same time the temperature rises)
· When an analog signal changes it loses the original information
technology breaks information into pieces and shows those pieces as numbers (the music on a compact disc is stored digitally as a series of numbers, each number representing the needed voltage for a specific instance)
· A digital signal is discrete (the voltage changes dramatically between one extreme and the other) so at any time, the signal can be considered "high" (binary 1) or "low" (binary 0)
sampling rate
To record information digitally, one needs to take many measurements of the information; the number of measurements of information taken per second
when analog information is converted into a digital format by breaking it into pieces
binary numbers
All information in a computer is stored and managed as
A single binary digit is called a bit
base value
The base value of a number system tells us how many digits are available to use and what the place value of each digit in a number is
A digital signal is discrete (the voltage changes dramatically between one extreme and the other) so at any time, the signal can be considered "high" (binary 1) or "low" (binary 0)
base 16
two or more computers connected together so they can exchange information
file server
One of the computers on the network that stores programs and data needed for many of the other computers
point-by point connection
when two computer are connected and are close together (every computer is directly connected by wire to every other computer in the network)
network address
identify individual computers on a network
divided messages that are grouped to make it easier to send info across a network (zip-file is an example)
A LAN is a local area network which is designed for short distances and a limited amount of computers, aka an office, while a WAN is a wide area network designed to connect two or more LAN's across longer distances (aka branches of offices)
The internet
created by the department of defense and ARPA. Stands for internetworking.
A protocol is a set of rules about how two things communicate. The internet sets a protocol called TCP/IP which stands for Transmission Control Protocol/ Internet Protocol. The IP defines how info is formatted and transferred. The TCP sorts and finds any lost information
IP Address
unique number for every computer connected to the internet. Ex.
TLD- top level domain
programming statements
which execute the program. Java is
which means that objects make up the basic pieces of the program.
Central processing unit, the device that executes the individual commands of a program
Input/ Output devices, allow a person to interact with the computer (keyboard, mouse, monitor)
Random access memory, basically like main memory (which holds the software while it is being processed by the CPU), data can be both written to it and read from it
Read only memory, information on ROM can't be changed because it's read only memory (CD ROM)
OS-operating system, the main software of a computer, it does two things, 1. Provide a user interface and 2. manages computer resources (like the CPU and main memory). The OS decides when programs can run, where they are loaded into memory, and how hardware devices communicate (Examples: Windows 7, Max OS X)
Graphical User Interface
almost all devices in a computer system other than the CPU and main memory
binary numbers
number system with a base value of two (only has two digits - 1 and 0)
Hexidecimal Numbers
base 16, uses A-F to represent decimal values 10-15
Wide Area Network
Basic Input/ Output System
Single In- Line Memory Module
Video RAM (Video Random Access Memory)
the central circuit board
arithmetic logic unit
smallest visible screen element, thousands of pixels make up a screen.
Software that runs products and units of a computer.
American Standard Code for Information Interchange.
(Transmission Control Protocol/ Internet Protocol) Internet software must follow these set of protocols. The IP determines how information is formatted and transferred. The TCP handles out of order or lost pieces of information
A software tool that loads and formats Web documents for viewing.
A set of software components that adds capabilities to a larger software application
It is basically a links page where you can connect to other websites
(HyperText Markup Language) It is a Web server where documents are formatted