Computer Fundamentals
Computer
A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations automatically. Modern digital electronic computers can perform generic sets of operations known as programs. These programs enable computers to perform a wide range of tasks.
Features/Characteristics of Computer
a. Speed: A computer works with much higher speed and accuracy compared to human while performing mathematical calculations. Computers can process millions of instruction per second. The time taken by computers for their operations is microseconds and nanoseconds.
b. Accuracy: Computer performs calculations with 100% accuracy. Errors may occur due to data inconsistency or inaccuracy.
c. Diligence: A computer can perform millions of tasks or calculations with the same consistency and accuracy. It doesn't feel any fatigue or lack of concentration. Its memory also makes it superior to that of human beings.
d. Versatility: Versatility refers to the capability of a computer to perform work in different software at the time, works with same accuracy and efficiency.
e. Reliability: A computer is reliable as it gives consistent result for similar set of data i.e., if we give same set of input any number of times, we will get the same result.
f. Automation: Computer performs all the tasks automatically i.e., it performs tasks without manual intervention.
g. Memory: A computer has built-in memory called primary memory where it stores data. Secondary storage are removable devices such as CDs, pen drives, etc., which are also used to store data.
Various Types of Computer
On the basis of Size
a. Digital Computer
A digital computer is considered to be a calculating device that can perform arithmetic operations at enormous speed. It is defined as a device that operates upon information/data. It operates on data, including magnitudes, letters, and symbols, that are expressed in binary code-i.e, using only the two digits 0 and 1.
Difference Between Analog and Digital Computer
| Analog Computer | Digital Computer |
|---|---|
| Analog computer works with continuous values. | Digital computers works with discrete value(0,1). It can work only with digits. |
| It has no state. | It has two states on and off. |
| It can perform certain types of calculations. | Its speed of calculations is very high. |
| Analog computer is used for calculations and measurement of physical quantities such as weight, height, temperature and speed. | Digital computer is used to calculate mathematical and logical operations. |
| Examples: Thermometer, analog clock, older weighing machines, car speedometer etc. | Examples: Digital watches, (mini, micro, mainframe) computers. |
Block diagram of a Computer System
A block diagram represents the components of a computer system and their connections. Here is a simplified block diagram of a computer system.
Input Device: These devices, such as keyboard and mouse, allow users to provide input to the computer system.
Central Processing Unit(CPU): The CPU is the brain of the computer the executes instructions and performs calculation.
Memory: It stores data and instructions that are currently being processed by the CPU. It includes RAM(Random Access Memory) and cache memory.
Storage device: These devices, like hard drives and solid state drives, provide long-term storage for data and programs.
Output device: Devices like monitors and printer display or present the results of the computer's processing.
The computer system works by receiving input from the user through input devices, processing the input using the CPU and memory, accessing data and instructions from storage devices, and producing output through output devices. The software provides the necessary instructions for the CPU to perform specific tasks, and the hardware components facilitate the execution of those instructions.
Hardware
Computer hardware refers to the computer's tangible components or delivery system that store and run the written instructions provided by the software. Computer hardware includes the physical parts of a computer, such as the case, central processing unit, random access memory, monitor, mouse, keyboard, computer data storage, graphics card, sound card, speakers and motherboard.
Difference Between Device Drivers and Firmware
| Device Drivers | Firmware |
|---|---|
| To help in the communication between an operating system and the hardware. | Defines the function ability of the hardware. |
| It is stored in the memory space allocated by the operating system. | It is stored in the volatile memory of the hardware. |
| It acts as intermediary between the OS and hardware. | It is coded in the hardware and handles the basic input and output function. It handles the integral function of the hardware. |
| It is more devices dependent. | It doesn't depend on any device, it takes care of the internal functions of the hardware. |
| The best example is the graphics driver that communicate with your OS to control your video card. | A Basic Input Output System(BIOS) can be considered as the best example of the firmware. |
Peripheral Device
A peripheral device is an internal or external device that connects directly to a computer or other digital device but doesn't contribute to the computer's primary function, such as computing. It helps end users access and use the functionalities of a computer.
Software
Software is a set of instructions or commands that tell a computer what to do. In other words, the software is a computer program that provides a set of instructions to execute a user's commands and tell the computer what to do. For example like Paint, Photoshop, MS Word etc.
Various Types of Software
System Software
System software are the computer software designed to operate and control the computer hardware and to provide the platform for running application software. The system software can be separated can be into two different categories, operating system and utility software.
Application Software
Application software is a set of programs designed to perform a specific task. It does not control the working of a computer as it is designed for end-users. Application software can be easily installed or uninstalled as required. An application software helps the user to execute either a single or multiple tasks. The different types of application software include database software, multimedia software, word processing software etc.
Computer Memory
Computer memory is just like the human brain. It is used to store data/information and instructions. It is a data storage unit or data storage device where data is to be processed and instruction's required for processing are stored. It can store both the input and output can be stored here.
Various Types of Memory
a. Primary Memory(Main Memory): Primary memory is also known as main memory or may also refer to "Internal memory", and primary storage. All those types of computer memories that are directly accessed by the processor using data bus are called primary memory. That allows a processor to access stores running programs and currently processed data that stored in a memory location.
- RAM (Random Access Memory)
- SRAM (Static Random Access Memory)
- DRAM (Dynamic Random Access Memory)
- ROM (Read Only Memory)
- PROM (Programmable Read Only Memory)
- EPROM (Erasable Programmable Read Only Memory)
- EEPROM (Electrically Erasable Programmable Read Only Memory)
The Word "RAM" stands for "Random Access Memory" or may also refer to short-term memory. It's called "random" because you can read store data randomly at any time and from any physical location. It is a temporal storage memory. RAM is volatile that only retains all the data as long as the computer powered. It is the fastest type of memory. There are two types of RAM.
ROM is the long-term internal memory. ROM is "Non-Volatile Memory" that retains data without the flow of electricity. ROM is an essential chip with permanently written data or programs. It is similar to the RAM that is accessed by the CPU. ROM comes with pre-written by the computer manufacture to hold the instructions for booting-up the computer. There are three types of ROM.
b. Secondary Memory(Auxiliary Memory): Secondary memory is also known auxiliary memory. The secondary memory is accessed indirectly via input/output operations. This memory is also called permanent, external, stable or persistent memory.
The list of any ten MS DOS Commands with their functions
Here are ten MS-DOS commands with their functions.
a. DIR: Lists the files and directories in the current directory
b. CD: Changes the current directory
c. MD: Creates a new directory
d. RD: Removes an empty directory
e. COPY: Copies files from one location to another
f. DEL: Delete files
g. REN: Rename files
h. TYPE: Displays the contents of a text file
i. FORMAT: Formats a disk or drive
j. CHKDSK: Checks a disk for errors and displays a status report
Multimedia
Multimedia is a form of communication that uses a combination of different content forms such as writing, audio, images, animations, or video into a single interactive presentation.
Components of Multimedia are:
Text: The form in which the text can be stored can vary greatly. In addition to ASCII based files, text is typically stored in processor files, spreadsheets, databases and annotations on more general multimedia objects.
Graphics: There is great variance in the quality and size of storage(Image file format) for still images(Bitmap - gif, jpg, bmp) (Vector - svg, pdf, swf, ps). Digitalized images are sequence of pixels that represents a region in the user's graphical display.
Audio: An increasingly popular datatype(audio file format) being integrated in most of applications is Audio. Its quite space intensive. One minute of sound can take up to 2-3 Mbs of space. Several techniques are used to compress it in suitable format.
Animation: It involves the appearance of motion caused by displaying still images one after another. Often, animation is sued for entertainment purposes. In addition to its use for entertainment, animation is considered a form of art. It is often displayed and celebrated in film festivals throughout the world. Also used for educational purposes.
Video: One on the most space consuming multimedia data type is digitalized video. The digitalized videos are stored as sequence of frames. Depending upon its resolution and size a single frame can consume upto 1 MB.
