Computer Fundamental

Figure: Casing Structure Casing is a rectangular metallic box which provides framework for various components inside it. Various components such as motherboard, hard disk, CD-ROM, SMPS etc. are inter-connected to each other and fixed to the casing. The front side (Panel) of casing has 2 switches, power and reset keys. Similarly 2 LED, one for power and other for Hard Disk. There are other ports such as USB and audio ports in most casing of today. At the backside there is a box called SMPS, which is used to supply power. Similarly there are temporary block panels for different input/output…

Figure: Power Supply Box of Desktop Computer Computer is an electronic device which operates by using current. Computer is supplied 230 volt AC current which is converted to 110 volt DC current. Various components of computer such as Hard-Disk, CD-ROM, USB port, serial port, keyboard, mouse etc. needs current to operate. The computer has a power supply box known as SMPS (Switched Mode Power Supply) at the back-side of the casing. 230v AC current is supplied to the SMPS which again convert it to 110v DC current. The converted DC current is supplied to the motherboard and other components through…

Virtual memory is not only physically existing memory. It is created by operating system in the partition of hard disk. When operating system is installed for first time, the system automatically allocate some space in partition which is used as virtual memory. Virtual memory is used to ease program loading in RAM by creating more space in RAM and moving back unnecessary programs to virtual memory. When more program is to be executed than the allocated free space in RAM, in such case virtual memory is used to move unnecessary or unused program for RAM. This created space in RAM…

Cache memory is a small size memory placed inside the processor. The main function of cache memory is to reduce the access time of loading previously run program. Once run programs are temporarily stored in cache memory so that when it is run again, the access (loading) time decreases. Cache memory is of 2 types; Internal cache (L1) and External cache (L2). Generally, the internal cache storage size is small comparison to external cache. It is found that internal cache size is 36KB while external cache size ranges from 256KB-5MB.The notation of cache mentioned on outer surface of processor is…

Flash memory is a small chip memory which is a type of EEPROM. It can store data in the form of video, images and other format. The stored data can be read and deleted to store new one. The deletion of data is carried by high speed current of device. Hard Disk Fig. Structure of Hard Disk Hard disk is a secondary memory or storage device which can store large amount of data which can be stored for long time period without need of any power backup. A hard disk is used to store operating system, programs data and information.…

ROM is a small size primary memory used in computer system. The data or information stored in ROM can be used (read) as many times as required but the stored content cannot be modified. ROM also needs power backup to hold data or information settings. BIOS is a small size memory used as ROM in computer which provides Input/Output system information during computer booting. It is made of semi-conductor material so it is also known as CMOS (Complementary Metal Oxide Semi-Conductor). The CMOS is placed in motherboard and is powered by a 3 volt DC battery known as CMOS battery.…

RAM (Random Access Memory): RAM is an essential memory used in computer system which helps during booting of computer system. So it is known as primary or main memory. The data or information stored in RAM is temporary time period, when computer is powered ON, data or information start to load in RAM but data or information are lost once computer is switched OFF. All data or information reaches to RAM in the form of current. So it is also known as volatile memory. Data or information in RAM can be read or write. The stored data is accessed in…

Memory is a unit place where data or information is stored for some time period. Some memory can store data for temporary period while others can store for permanent time period. Similarly some memory require power backup to hold data while others do not require power backup. Small size to large size data holding memories are used in computer. The storage capacity of memory is measured in Byte. 1 Byte = 8 Bit Depending on memory usage, memory is classified into two types:- Primary Memory: Primary memory refers to RAM and ROM, which are necessary to boot (Run) computer for…

Generation of computer shows or describes different type of computers invented or manufactured using different technologies. Similarly, generation also describes shape, size and capacity of computer changed during different time frame. 1] First Generation (1940-1956): Vaccum Tubes Characteristics: - The first generation computers were based on vaccum tubes. - The first generation computers were very large require a lot of space and consume more electricity. - Since, they were big, they were not portable. - They lacked in versatility and speed. - These machines were unreliable and prone to frequent hardware failure. - These machines were programmed using machine language…

The computer types can be classified according to the signal usage, size and speed. According to signal used by computers computers are two types:- 1] Analog  Computer:- An analog computer is that which uses analog signal as input, It uses an infinite number of voltage or current values. Characteristics of a analog computer are:- - It operates by measuring. - It require physical analog values. - It functions on continuous varying quantities. - The output is usually represented in the form of graph. - The accuracy of output is poor. - It has limited memory space. - The speed of…