Exam 1 Terms (Key Concepts) Flashcards
What does a computer system consist of?
hardware and software that work in concert to help us solve problems.
What is hardware?
Components of a computer system that are the physical, tangible pieces that support the computing effort.
They include chips, boxes, wires, keyboards, speakers, disks, memory cards, etc.
What is software?
Programs and the data that programs use.
The intangible counterpart to the physical hardware components. Together they form a tool that we can use to help solve problems.
What are the key hardware components in a computer system?
central processing unit (CPU) - a device that executes the individual commands of a program
input/output (I/O) devices - devices that allow a human being to interact with the computer (keyboard, mouse, trackpad, and monitor)
main memory - the storage device that holds the software while it is being processed by the CPU
secondary memory devices - hardware storage devices that store software in a relatively permanent manner. (hard disk, USB flash drive)
How does information move along the basic hardware components of a computer?
The program is stored on some secondary memory device, such as a hard disk. When you instruct the computer to execute your program, a copy of the program is brought in from secondary memory and stored in main memory. The CPU read the individual program instructions form main memory and then executes the instructions one at a time until the program ends.
The data that the instructions use will be added together and stored in main memory. They are either brought in from secondary memory or read from an input device such as a keyboard.
During execution, the program may display information to an output device such as a monitor.
What is the function of an operating system in a computer?
It is the core software of a computer to make sue the computer’s easy to use and to ensure it runs efficiently:
1- It provides a user interface that allows the user to interact with the machine
2- It manages computer resources such as the CPU and main memory. It determines when programs are allowed to run, where they are loaded into memory and how hardware devices communicate.
Examples are MacOS for Apple computer, Windows for Microsoft computers, etc
What is an application?
A generic term for any software other than an operating system. Each program has it’s own user interface that allows the user to interact with that particular program.
Examples are Web browsers, Word processors, Missile control systems, etc.
What is Graphical User Interface (GUI)?
Software that allows the user to interact with a program using mouse-driven controls
sometimes called point and click interfaces
Examples are window, icons, menus, checkboxes, radio buttons, sliders, buttons
What is an Analog?
A technique used to store and manage information that is continuous, in direct proportion to the source of the information
Example is a sound ware and an electronic analog signal (represents the wave)
How do digital computers store information?
By breaking the information into discrete pieces and representing those pieces as numbers.
example: music on a compact disc is stored digitally, as a series of numbers. Each number represents the voltage level of one specific instance of the recording.
How can we digitize information?
Sampling: When analog information is converted to a digital format by breaking it into pieces
Example: a sentence of text is stored on a computer as a series of numbers, where each number represents a single character in the sentence. Every letter, space, digit and punctuation symbol has been assigned a number.
How is binary used?
To store and move information in a computer because the devices that store and manipulate binary data are inexpensive and reliable.
binary is the base-2 number system. Modern computer systems store information as strings of binary digits (bits)
How many bits can be represented?
There are exactly 2^N permutations of N bits. Therefore, N bits can represent up to 2^N unique items.
Representing information on a computer boils down to the number of items there are to represent and determining the way those items are mapped to binary values.
Ex. How many bits would be needed to represent 195 countries of the world? Seven wouldn’t be enough, because 27 equals 128. Eight bits would be enough, but some of the 256 permutations would not be mapped to a country.
What is computer architecture?
The structure and interaction of the hardware components of a computer.
Information travel between components across a group of wires called a bus (group of wires in the computer that carry data between components such as the CPU and main memory)
What is an address?
A unique number associated with a memory location in a computer’s main memory.