- •1)Different types of computer
- •2)How can data be stored?
- •3)Peripheral devices
- •4)Operating systems
- •Classification of Operating systems
- •5)Application programs
- •6)Network communication
- •7)A global computer network: the Internet
- •8) The Internet Service: The World Wide Web
- •9)Searching for Websites
- •10)Websites: Designing WebPages
- •11)Data Security: How does a virus operate ?
- •12)Data Security: How to prevent a computer from crimes and disasters?
- •13)Recent developments in it
- •14)How to become a professional in computing?
- •15)The future in it
1)Different types of computer
Today computers play big role in our life. Thanks to computer technology, we have been able to achieve storage and processing of huge amounts of data. There are many types of computer. Depending on their processing powers, size and area of use, they have been classified into various types. Based on the operational principle, computers can be classified as analog and digital. Based on their processing powers, they can be categorized as mainframe and microcomputer. Based on the usage, they can be grouped under desktop computers, laptops, tablets, netbooks, personal digital assistants (PDAs) and even tiny wearable ones.
Microcomputers: A computer with a microprocessor and its central processing unit is known as a microcomputer
Desktop Computers: A desktop computer is intended to be used on a single location.
Laptops: Similar in operation to desktop computers, laptop computers are miniaturized and optimized for mobile use.
Netbooks: They fall in the category of laptops, but are inexpensive and relatively smaller in size
Tablets: Tablets are mobile computers that are very handy to use. They use the touch screen technology.
2)How can data be stored?
Clusters and Data Storage
A computer stores data in clusters on the hard drive. Each cluster is a pie slice-looking area that holds a certain amount of data. The amount of data that can be stored in each cluster is dependent on the operating system. For example, the FAT 16 operating system has 32KB clusters, the FAT 32 has 4KB clusters and UNIX generally has 1KB clusters. These cluster sizes also depend on the size of the hard drive.
Smaller clusters allow the computer to handle data more efficiently. Typically, when a file is saved to a cluster it is the only file at that location. The computer keeps track of the "address" of that file, which tells the computer exactly where the data is stored. If a 2KB document is stored on a FAT16 operating system, then 32KB of space is allocated to that file, while on a FAT32 system it may only take 4KB of space.
Partitions and Data Parameters
During its installation process, the operating system creates a start and stop point for your hard drive. This is called a partition. Without the start and stop points, the computer will not know where to start or stop looking for data. A computer can have several partitions on a single hard drive. Having several partitions can help the user with organizational implementation, security concerns, additional virtual memory or just preferential considerations.
Impermanent Data
Data is stored onto the hard drive magnetically. Do not believe that data stored on a hard drive is permanent, because it is not. A computer cannot sit for years without losing any of its data. Living around highly magnetic sources such as power lines can decrease the life of the data on your hard drive. The Earth's self-produced magnetism will eventually negatively affect the hard drive. That is why it is a good idea to burn important information to a DVD; it has a much longer storage life cycle.