Computers for Today Jason Fan Essential Computer Concepts What is a Computer? A computer is a device that: Accepts input Processes data Stores data Produces output What is a Computer? A Computer System is made up of: Hardware—the physical components
A computer is a device that:
A Computer System is made up of:
Architecture or configuration is the design of the computer.
As in, what does the computer consist of?
Specification is the technical detail about each component.
As in, how big is the monitor?
The hardware, software, and you work together to complete tasks.
The data you type into the computer is called input.
The result of the computer processing your input is called output.
The categories of computers are:
Personal computers are used for general computing tasks and fit the needs of most users
Hand-held computers fit in the palm of your hand and run on batteries.
Mainframes are used by companies to provide centralized storage, processing, and management for large amounts of data.
Supercomputers are the largest and fastest of computers, and can process an enormous volume of data.
Computer hardware includes:
Some input devices are:
Output devices are:
Monitors and Printers are common output devices.
CRT monitors and LCD (or flat panel display) monitors are two types of monitors.
Factors that influence a monitor’s quality are:
Storage and memory capacity is the amount of data the storage device can handle.
Computer memory is a set of storage locations on the motherboard.
There are four types of memory:
RAM is temporary memory that is constantly changing while the computer is on.
Virtual memory is extra memory that simulates RAM if more is needed.
Read-only memory (ROM) is the permanent storage location for a set of instructions the computer uses.
CMOS memory is semi-permanent information about where essential software is stored.
A storage device receives data from RAM and writes it on a storage medium. Later, it can be read and sent back to RAM.
Data is stored as files.
Executable files tell computers how to perform specific tasks.
Data files are created by the user, usually with software.
Files are kept on storage devices.
Magnetic storage devices and
Optical storage devices.
Some common magnetic storage devices are:
A floppy disk
Some common optical storage devices are:
CD-ROMs are for “read-only” access.
CD-Rdrives allow you to record data on a CD-R disk.
CD-RW drives allow you to write data on a CD-RW disk and access and modify data.
Data Communications is the transmission of text, numeric, voice, or video data from one computer to another.
The four essential components of data communications are:
A sender is the computer that originates the message.
The message is sent over a channel, such as a telephone.
The receiver is the computer at the message’s destination.
Protocols are the rules that establish the transfer of data between sender and receiver.
The data bus is the communication between microprocessor, RAM, and the peripherals.
An external peripheral device has a port or cable that connects it to the computer.
Each port connects to a controller card, which plugs into expansion slots.
The transmission protocol is handled by a device driver.
Microcomputers have several types of ports:
A parallel port transmits data eight bits at a time, and is often used to connect a nearby printer.
A serial port transmits data one bit at a time, and often connects a mouse, keyboard, or modem.
A SCSI (“scuzzy”)connection can allow many devices to use the same port, and are popular on Macs and notebooks.
MIDI cards are used to record and play back musical data.
Computer expansion ports
USB (Universal Serial Bus) ports replace numerous connectors with one plug and port combination. The device you install must have a USB connector.
A network connects one computer to other computers and peripherals.
In a local area network (LAN), computers and peripherals are close to each other.
A client/server network is a network with a file server. A file server acts as the central storage location.
A network without a file server is a peer-to-peer network. All of the computers are equal.
Each computer that is part of the network must have a network interface card and network software.
Then it becomes a workstation.
Any device connected to the network is called a node.
Telecommunications is communicating over a telephone. In the telecommunications process, the modem converts digital signals to analog signals at the sending site and a second modem converts them back at the receiving site.
The Internet is the world’s largest network.
E-mail and the World Wide Web are two benefits of the Internet.
A hyperlink is a place on a Web page allowing you to connect to a particular file.
A Web browser is
the communications software that allows you to navigate the WWW.
Software is the instructions and data that direct the computer to accomplish the task. It can refer to a single program or a package.
System software helps the computer carry out its basic operating tasks.
Application software helps the user carry out a variety of tasks.
The four types of system software are:
The operating system controls the I/O or input/output, the flow of data from microprocessor to memory to peripherals.
The operating system makes multitasking possible.
Some types of system software include:
Application software enables you to perform specific tasks. Application software includes:
Document production software includes word processing, desktop publishing, and Web authoring software that assist you in writing and formatting documents.
It often has grammar and spell-checking, thesaurus, search and replace, and template features.
With spreadsheet software, you can create formulas that perform calculations. Spreadsheet software creates worksheets with columns and rows. The intersection of a column and row is a cell.
Database management software creates structured databases to contain information.
Graphics and presentation software allow you to create illustrations, diagrams, and charts to be presented or transmitted. Most allow you to include graphics.
Multimedia authoring software allows you to record digital sound files, video files, and animations that can be included in presentations and other documents.
Object linking and embedding (OLE) is the ability to use data from another file, called the source.
This integration between applications has become an important skill in business.