People hardly bother about the insides of a computer. All that matters is the software and its updates. The building blocks or the foundation of a computer is often forgotten. What are microprocessors? Ever heard of them? Okay, you must've at least heard about Pentiums, Athlons and Celerons. Yes, these are microprocessors under various brand-names. Microprocessors are rightly termed as the heart and soul of a normal computer, be it a laptop or a desktop. Being the Central Processing Unit (CPU) of a computer, all microprocessors do the same work and that too in a similar fashion. EVOLUTION A microprocessor by itself is a finished computation unit and is embedded on a chip. Intel 4004, the first ever microprocessor was unleashed in 1971. Compared to modern microprocessors, the 4004 was a weakling. All it could do was add or subtract and that too just 4 bits at a time. But the fascinating fact was that unlike until then, all components were integrated into a single chip. The Intel 4004 found its application in early electronic calculators. With time, Intel progressed to build the 8-bit Intel 8080 microprocessor. This was the first to make its way into a home computer system in 1974. Intel moved on to build more advanced microprocessors. There came the 8088, 80286, 80386 and eventually the Intel Pentium series. The work done by the 8080 and Pentium is pretty much the same, except that the Pentium does it about 5000x faster. WORKING So how do microprocessors work? Well, a microprocessor actually performs three basic tasks: 1.The microprocessor has a unit called the Arithmetic and Logic Unit (ALU). This unit helps it to perform basic addition, subtraction, multiplication and division. 2.A microprocessor is able to move data through memory locations. 3.It is equipped to finalize decisions and jump to a fresh set of instructions as per the decisions made. These are the three tasks performed by any microprocessor regardless of complex activities done by it. A microprocessor essentially contains the following: Address Bus : This sends an address to the memory. Data Bus : This sends and receives data to and from memory. RD/WR Line : The RD (read) line tells the microprocessor if the memory wants to set the addressed location. The WR (write) line tells the memory if it wants to get the addressed location. Clock Line : This allows a clock pulse to sequence the microprocessor. Reset Line : Execution is restarted and the program counter is reset. PERFORMANCE   The address bus and data bus of a microprocessor could be 8, 16 or 32 bits wide. This gives the meaning that, if we have a microprocessor with address bus and data bus 16 bits wide, the microprocessor can address (2^16)=65536 bytes of memory and can read or write 16 bits of memory in a go. Even the least sophisticated microprocessor will have a lot of instructions that can be assigned to it. These instructions originally exist as patterns of bits. But patterns as such are very difficult to remember. Hence, specific words are assigned for patterns to make things easier for the programmer. The collection of these words is what we call the Assembly Language. The programmer uses the assembly language which is then converted to bit pattern by the 'assembler' in the microprocessor. The bit pattern can easily be executed and the microprocessor starts its works. Microprocessor performance is largely determined by the number of transistors used in it. Larger the number of transistors in a microprocessor, faster is the clock speed. It is the clock speed that determines the performance of a computer. People often compare the disk space or RAM while buying a computer. This is a blunder. The processor's clock speed should be the main concern. If the clock speed is low, the computer wouldn't be able to utilize the RAM efficiently.