: A program or software is a set of systematic instructions written consistently in computer language to solve a problem. In other words , software is a set of instructions written in computer language so that the computer can understand and solve the problem. The software cannot be seen or touched. Hardware is the instrument used to make the computer's external infrastructure. That is, all the parts of the computer that can be touched or touched are called hardware. Hardware and software have to work together to get effective results through computer. One without the other is obsolete. Software tells you what hardware will do. Hardware is the body and software is the brain. When a mosquito is bitten on the leg, the brain realizes it and signals the hand to kill the mosquito. Here the brain is using any part of the body. Similar software uses hardware on computers. For example , creating a document in MS Word will save it to a hard disk and pen drive if you order it with a name and it will be printed if you order it to be printed on a printer. Here the hardware will work under the direction of the software. Operating system software is the lifeblood of a computer. If there is no life in the body, it will not do any work. Similarly, without operating system software, computer work will not be useful. Then no other software will work in it. So we can say by comparison with human beings: Hardware = body software = soul and brain The brain controls every part of the body. That's how software controls hardware. Software is used to make computer hardware work and to solve any problem by computer. Basically, the use of appropriate software makes the lifeless parts of the computer work. Without software, computer hardware is useless and nothing but rubbish. That's why both hardware and software are needed to get effective results through computer. Hardware and software complement each other. Different types of software can be loaded on the same hardware i.e. computer for different tasks. In general, the cost of computer hardware, except for upgrading, is one-time , while the cost of software is ongoing. A complete computer system is a combination of user , hardware and software.