In this article we will discuss about:- 1. Meaning of Computer 2. Types of Computers 3. Some Other Terms of Computer 4. External Storage Devices 5. Computer Programs 6. Advantages of Computer in Genetics 7. Limitations.
Meaning of Computer:
Computer refers to an electronic device that can transmit, store and process information or data in a desired form. The computer aided study of biology particularly genetics and molecular biology is called bioinformatics.
Now the science of bioinformatics is gaining increasing importance in life science especially in the field of molecular biology and plant genetic resources. It is the interface between computer and biology. In other words, it is the application of information technology in the study of biology. It has wide applications in handling data related to plant genetic resources.
Types of Computers:
Based on size and capacity, computers are of four types, viz:
(1) Super computers.
(2) Mainframe computers,
(3) Minicomputers, and
These are briefly discussed as follows:
1. Super Computers:
Super computers have extremely large storage capacity. Its speed is at least 10 times faster than other computers. Such computers are generally used for large scale numerical problems in scientific and engineering disciplines. These computers can process billions of instructions per second.
2. Mainframe Computers:
Mainframe computers can also process data at very high speeds i.e., hundreds of million instructions per second and they are also quite expensive. Normally, they are used in banking, airlines and railways, etc. for their applications.
3. Mini Computers:
Mini computers are lower to mainframe computers in terms of speed and storage capacity. They are also less expensive than mainframe computers. Some of the features of mainframes will not be available in mini computers. Hence, their performance also will be less than that of mainframes.
4. Micro Computers:
Micro-computers are smallest general purpose computers. Such computers have been designed for use by one person at a time and, therefore, are known as personal computers. A computer designed for use by an individual or single person is called personal computer. In price, personal computers are relatively cheaper.
They are used by businessman for word processing, accounting, desktop publishing, and for running spreadsheet and database management applications. Personal Computers include desktop computers and portable computers. Portable computers include desktop computers, notebook computers, laptop computers, palmtop computers and tablet computers.
These are explained as follows:
(i) Desktop Computer:
A computer designed to keep on top of a desk and work is referred to as desktop computer. Desktop models designed to be very small are sometimes referred to as slim line models.
(ii) Notebook computer:
An extremely light weight (less than 6 pounds) small personal computer which can fit easily in a briefcase is called notebook computer. In terms of computing power, modern notebook computers are nearly equivalent to personal computers. They have the same CPUs, memory capacity, and disk drives.
Notebook computers cost about twice as much as equivalent regular-sized computers. Notebook computers come with battery packs that enable you to run them without plugging them in. However, the batteries need to be recharged every few hours.
(iii) Laptop computer:
A small, portable computer designed to keep on your lap and work is called laptop computer. Nowadays, laptop computers are more frequently called notebook computers. Laptop computers are portable computers.
They are lightweight computers with a thin screen. They are also called as notebook computers because of their small size. They can operate on batteries and hence are very popular with travelers. The screen folds down onto the keyboard when not in use.
A small sized computer designed to keep on palm and work is known as palmtop computer. Palmtops are in limited use, but they are used as phone books and calendars. Palmtops that use a pen rather than a keyboard for input are often called hand-held computers or personal digital assistant (PDA). Because of their small size, most palmtop computers do not include disk drives.
(v) Tablet Computer:
A tablet computer, or a tablet, is a mobile computer, larger than a mobile phone or personal digital assistant. A tablet PC is a wireless, portable personal computer with a touch screen interface. It is smaller than a notebook computer but larger than a smart phone. It is a type of notebook computer that has an LCD screen on which the user can write using a special-purpose pen, or stylus.
The handwriting is digitized and can be converted to standard text through handwriting recognition, or it can remain as handwritten text. Tablet PCs also typically have a keyboard and/or a mouse for input.
A tablet computer may be of three types, viz:
(b) Hybrid, and
These are defined as follows:
(a) Convertible Tablet:
It has typically a display that rotates 180 degrees and can be folded to close, screen up, over the integrated keyboard. Convertible models may allow user input through a variety of methods in addition to the hardware keyboard, including natural handwriting with a stylus or digital pen and typing through a screen-based software keyboard.
(b) Hybrid Tablet:
It is like a regular notebook but with a removable display that functions independently as a slate.
(c) Rugged Tablet:
It is a slate-like model that is designed to withstand rough handling and extreme conditions. Rugged tablets are usually encased in a protective shell and have shock-protected hard drives.
Architecture of a Micro-Computer:
A microcomputer consists of four components, viz., microprocessor, input, output and memory. These components are organized around a common communication path called bus. The entire group of components is called a system or a microcomputer system.
A brief description of various computer components of presented as follows:
It is a semiconductor device consisting of electronic logic circuits. It is manufactured by using either large or very large scale integration technique.
It performs computing functions and consists of three units, viz:
(i) Arithmetic logic unit,
(ii) Register unit and
(iii) Control unit.
These are defined as follows:
(i) Arithmetic Logic Unit:
In this area of microprocessor, computing functions are performed on “data. The ALU performs arithmetic operations such as addition and subtraction and logic operations. Results are stored either in registers or in memory or sent to output devices.
(ii) Register Unit:
This area of microprocessor consists of various registers which are used primarily to store data temporarily during execution of program.
(iii) Control Unit:
The control unit provides necessary timing and control signals to all the operations in microprocessor. It controls the flow of data between the microprocessor and peripherals (including memory).
This is a medium or device that stores binary information such as instructions and data, and provides that information to the microprocessor as and when necessary. The memory is of two types, viz., read only memory (ROM) and read and write memory.
These are defines as follows:
(i) ROM [Read Only Memory]:
A memory that stores binary information during the operation of computer. This memory is used as writing pad to write user programs and data. The information stored in this memory can be read only.
(ii) [Read/Write Memory]:
It is also known as random access memory (RAM) and user memory. The information stored in this memory can be read and altered easily.
A device that transfers information from outside world to the computer. It includes key board.
Computer devices that transfers information from computer to outside world. It includes monitor and printer. The input and output devices of computer are jointly known as peripherals.
Some Other Terms of Computer:
Important technical terms which are widely used in relation to computer applications are defined here as under.
Bit. A binary digit, 0 and 1.
Byte. A group of eight bits.
Bus. A group of lines used to transfer bits between the microprocessor and the components of computer system.
Hardware. The physical components of computer such as key board, processing unit, monitor, mouse and printer.
Software. A group of program written for the computer to perform a task.
Nibble. A group of four bits.
Program. A set of instructions written in a specific sequence for the computer to accomplish a given task.
Word. A group of bits the computer can recognize and process at a time.
External Storage Devices of Computer:
Various media that are used to store information temporarily and transfer the same from one computer to another are referred to as external storage devices. Such devices are not permanently fixed inside a computer.
There are several advantages of external storage devices as given below:
(i) External storage devices provides additional storage other than that available in computer.
(ii) Data can be transported easily from one place to another.
(iii) It is useful to store software and data that is not needed frequently.
(iv) External storage also works as data backup.
(v) This back up may prove useful at times such as fire or theft because important data is not lost.
The commonly used external storage devices include floppy disk, compact disk, digital versatile disk, USB storage devices, SD cards, etc.
A brief description of all these devices is presented as follows:
1. Floppy Disk:
It is a thin plastic disk coated with magnetic oxide and looks like a phonograph. It is available in various sizes. Floppy disk has been replaced by other better storage devices such as CD, DVD, USB, SD card and external storage hard disk. Now floppy disks are no more in common use.
2. Compact Disk:
Compact disk is commonly known as CD. The speed of compact disk is much less than a hard disk. The storage capacity is 700 MB. There are three types of CDs as discussed below.
It is compact disk read only memory. It can be read only.
It was invented in 1990s. Using CD-R it is possible to write data once on a disk these are write once read many disks.
There is a limit on how many times a CD-RW can be written. Presently this limit is 1000 times. CD-RW drives are compatible with CD-ROM and CD-R.
3. Digital Versatile Disk:
It is commonly known as DVD. Its speed is much faster than CD but not as fast as hard disk. The standard DVD-5 technology has a storage capacity of 4.7 GB. The storage capacity changes with the standard used. Its storage capacity (4.7 GB) is much higher than a CD (700 MB). It is achieved by a number of design changes.
4. USB Storage Device:
This is a very handy storage device which has replaced floppy disk and is easy to carry. It is known as pen drive, handy drive and thumb drive. Now pen drives are widely used by all type of users such as students, teachers, scientists and business man. Pen drive is available in various capacities such as 1 GB, 2GB,4GB, 8GB, 16Gb and 32GB.
5. Secured Digital Card:
This is commonly called as SD card. It is an ultra-small flash memory card designed to provide high-capacity memory in a small size. SD cards are used in many small portable devices such as digital video camcorders, digital cameras, handheld computers, audio players and mobile phones. SD cards are in use since 1999.
They are available in capacities between 16 Megabytes and 1 Gigabyte. An SD card typically measures 32 x 24 x 2.1 mm and weighs approximately 2grams. SD cards are of different capacities and some of them combine input /output functions with data storage. USB pen drives and other storage like High Capacity SD cards (SDHC) use flash memory to store information.
6. External Hard Disk:
A hard disk drive (HDD; also hard drive, hard disk, or disk drive) is a device for storing and retrieving digital information, primarily computer data. Hard disks have very high speed, storage capacity and reliability. Hard disk is generally permanently fixed in the computer. Now external hard disks are available in various capacities. Such data storage disks are now being used by students, teachers and researchers.
Various micro-soft programs which are commonly used in crop improvement (genetics and plant breeding) include Microsoft Word (M.S. Word), Microsoft Excel (M.S. Excel), Microsoft Power Point (M.S. Power Point) and Internet.
These are briefly defined as follows:
(i) M.S. Word:
It is a very useful program for preparation of annual reports, project reports, writing research papers, varietal information system, plant genetic resources data base, etc.
(ii) M.S. Excel:
It is a software program which is useful for various types o; statistical and biometrical analyses. It can also be used for graphical and diagrammatic display of experimental results.
(iii) M.S. Power Point:
It is a software program which is widely used for preparation of slides and presentation of results in various scientific meetings.
It is very much useful in searching literature, chatting and online transactions.
Advantages of Computer in Genetics:
There are several advantages of bioinformatics in crop improvement programs. Main advantages are high speed, high accuracy, large storage capacity, automation capacity, etc.
Some important advantages are listed as follows:
1. High Speed:
The computers have very high speed. The calculations that take months together can be performed in few minutes with the help of computers.
2. High Accuracy:
The computer aided programs have very high level of accuracy. A computer practically never commits mistake on its own. The computer error results due to error in the programming and handling.
3. Better Planning:
Computer aided programs help in better planning of experiments and systematizing the information of PGR and breeding experiments.
4. Large Storage capacity:
Computers have very large storage capacity. The huge data of PGR and breeding experiments can be easily be stored in computer memory and other storage devices. Results of long term experiments can be stored in systematic manner.
5. Pictorial Presentation:
Computer aided programs permit pictorial presentation of various reports and research papers which make them more attractive.
Limitations of Computer:
There are some limitations of computer aided programs which as listed as follows:
1. Handling of computer programs requires high technical for executing various computer programs.
2. The data has to be very carefully transferred from register to the computer. Any mistake in data transfer will lead to mistakes in the results.
3. Computer viruses sometimes pose problems.
4. Mishandling of computers sometimes leads to deletion of entire information from the computer memory.