Wednesday, February 3, 2016
Monday, February 1, 2016
Computer Network
What is a Computer Network?
A computer network is a set of computers connected together for the purpose of sharing resources. The most common resource shared today is connection to the Internet. Other shared resources can include a printer or a file server. The Internet itself can be considered as a computer network.
Computer Network Defined a computer network is a set of connected computers. Computers on a network are called nodes. The connection between computers can be done via cabling, most commonly the Ethernet cable, or wireless through radio waves. Connected computers can share resources, like access to the Internet, printers, file servers, and others.
Types of Network Connections
Computer networks can be broken down historically into is a technique of connecting computers. The most common topology today is a collapsed ring. This is due to the success of a network protocol called the Ethernet. This protocol, or a network language, supports the Internet, Local Area Networks, and Wide Area Networks.
Star Topology
A star topology is a design of a network where a central node extends a cable to each computer on the network. On a star network, computers are connected independently to the center of the network. If a cable is broken, the other computers can operate without problems. A star topology requires a lot of cabling.
Bus Topology
A bus topology is another type of design where a single cable connects all computers and the information intended for the last node on the network must run through each connected computer. If a cable is broken, all computers connected down the line cannot reach the network. The benefit of a bus topology is a minimal use of cabling.
Collapsed Ring Topology
A similar topology is called a ring. In this design, computers are connected via a single cable, but the end nodes also are connected to each other. In this design, the signal circulates through the network until it finds the intended recipient. If a network node is not configured properly, or it is down temporarily for another reason, the signal will make a number of attempts to find its destination.
About mouse
Mouse is a national youth development nonprofit that believes in technology as a force for good. We empower all students to create with technology to solve real problems and make meaningful change in our world.Mouse opens opportunities for youth from under served communities and helps all students realize their full potential and the potential of technology to make a positive impact in their schools and communities.We are committed to increasing diversity in STEM and believe it is critical to support a diverse pool of talent to fuel the nation's future.
Computer keyboard
A computer keyboard is a typewriter-style device which uses an arrangement of buttons or keys to act as a mechanical lever or electronic switch. Following the decline of punch cards and paper tape, interaction via teleprinter style keyboards became the main input device for computers.
A keyboard typically has characters engraved or printed on the keys and each press of a key typically corresponds to a single written symbol. However, to produce some symbols requires pressing and holding several keys simultaneously or in sequence. While most keyboard keys produce letters, numbers or signs characters, other keys or simultaneous key presses can produce actions or execute computer commands.
Sunday, January 31, 2016
What is Computer Graphics?
Statements in QBASIC
Statements in QBASIC
A statement (for the QBASIC) is a set of instructions written by using keywords or commands of QBASIC. Every programming language uses keywords as a statement with certain syntax. The keywords have specific meaning in the QBASIC programming. The statements are the first stored in the memory and executed only when the RUN command is given.
Different statements used in QBASIC are as follows:
CLS Statement
The CLS statement clears the screen. If you write CLS statement in the middle of the program then you cannot see the outputs generated before execution of CLS because it clears the screen.
Syntax: CLS
LET Statement
LET is an assignment statement. It is used to assign the value to a variable. LET is an optional statement i.e. without using LET statement one can assign the value to a variable. The data type must match with the variable type otherwise type mismatch error will occur.
A statement (for the QBASIC) is a set of instructions written by using keywords or commands of QBASIC. Every programming language uses keywords as a statement with certain syntax. The keywords have specific meaning in the QBASIC programming. The statements are the first stored in the memory and executed only when the RUN command is given.
Different statements used in QBASIC are as follows:
CLS Statement
The CLS statement clears the screen. If you write CLS statement in the middle of the program then you cannot see the outputs generated before execution of CLS because it clears the screen.
Syntax: CLS
LET Statement
LET is an assignment statement. It is used to assign the value to a variable. LET is an optional statement i.e. without using LET statement one can assign the value to a variable. The data type must match with the variable type otherwise type mismatch error will occur.
Saturday, January 30, 2016
THE FIVE TYPES OF COMPUTERS
TYPES OF COMPUTERS
* Mainframe
- first type of computer used by government and businesses
- multiple tasks for many users simultaneously
- Large corporations
- Climate controlled rooms
- Hook-up to it through personal computer
- Examples government agencies accessing social security numbers/info
- National car rental company access info on anytime/where you have ever rented a car
- Credit card companies customer service
* Supercomputer
- Processes trillions of calculations per second
- Weather forecasting
- Crash testing
- Special effects in movies
- $100 million
- Why do people spend this much on a computer? save lives or will make more than it cost
* Minicomputers
- Popular in the 70 and 80
- Small to medium size companies
- Schools and small office companies (less than 100 people)
- Less than $100,000
- Now that PCs are so powerful, these are becoming OBSO.
* Personal Computers
- Exploded in the early 80
- Cost is always decreasing
- Use to have a lot of types now Apple and IBM compatible (Apple good for media)
- Rapid processing and relatively low cost
- Scientist, graphics, financial analyst, architects
- $2000-$9000
* Mainframe
- first type of computer used by government and businesses
- multiple tasks for many users simultaneously
- Large corporations
- Climate controlled rooms
- Hook-up to it through personal computer
- Examples government agencies accessing social security numbers/info
- National car rental company access info on anytime/where you have ever rented a car
- Credit card companies customer service
* Supercomputer
- Processes trillions of calculations per second
- Weather forecasting
- Crash testing
- Special effects in movies
- $100 million
- Why do people spend this much on a computer? save lives or will make more than it cost
* Minicomputers
- Popular in the 70 and 80
- Small to medium size companies
- Schools and small office companies (less than 100 people)
- Less than $100,000
- Now that PCs are so powerful, these are becoming OBSO.
* Personal Computers
- Exploded in the early 80
- Cost is always decreasing
- Use to have a lot of types now Apple and IBM compatible (Apple good for media)
- Rapid processing and relatively low cost
- Scientist, graphics, financial analyst, architects
- $2000-$9000