Input Unit takes data by input device. Any machine that feeds data into a computer is called input device. For example, a keyboard is an input device, whereas a display monitor is an output device. Input devices other than the keyboard are sometimes called alternate input devices. Mice, trackballs, and light pens are all alternate input devices. Input Unit converts any input Data into Binary format.
There are two kinds of memory and they are:
I. Primary memory
II. Secondary memory
Primary Memory:
Primary Memory is the main memory of a computer. Primary memory is the memory that can be directly accessed by the CPU which constantly interacts with it, retrieves data stored therein, goes through instructions and execute them as per the requirement. All the information, data and application are loaded there in uniform manner. It is also called Volatile Memory. RAM (Random Access Memory) is the primary memory.
There are two kinds of RAM and they are:
I. SRAM (Static Random Access Memory)
II. DRAM (Dynamic Random Access Memory)
Secondary Memory:
Secondary Memory is the additional memory of a computer. It is also called Non-Volatile Memory. ROM (Read Only Memory) is the secondary Memory.
There are two kinds of ROM and they are:
I. PROM (Programmable Read Only Memory)
For Example: Non writeable CD/DVD.
II. EPROM (Erasable Programmable Read Only Memory)
For Example: BIOS.
III. EEPROM (Electrically Erasable Programmable Read Only Memory)
For Example: Hard disk, writeable CD/DVD pen Drive etc.
CPU: CPU is the part of a computer (a microprocessor chip) that does most of the data processing. The abbreviation of CPU is Central Processing Unit.
We can divide CPU into two parts and they are:
I. ALU (Arithmetic and Logic Unit)
II. CU (Control Unit)
ALU: In computing, an arithmetic logic unit (ALU) is a digital circuit that performs arithmetic and logical operations.
CU: Full computer systems controlled by CU.
