Most computer systems only conduit code traced in the memory (ROM or RAM). Upgraded operating mechanisms are loaded on hard disks, or sometimes on LiveCDs, USB flash drives, or other non-volatile storage components. When one first switches on the computer, there is no trace of the operating system in memory. The computer’s hardware alone is unable to do intricate actions such as storing a program from the disk. There is also the requirement of the usage of a special tiny program called a bootstrap loader, bootstrap or boo loader. The only function of the program is to store other software for the operating system to make a start.



Sometimes, there is the requirement of the multi-stage boot loaders for the usage in which several small programs of augmenting intricacy summon each other, until the last of them can store the operating system. The name bootstrap loader emerges from the reflection of the one getting oneself up by bootstrapping. This method emerges from the old days of the computers. The old programmable computers were designed with array of toggle switches on the front panel to let the operator to insert the binary boot directions into the memory prior to the transfer of the control to the CPU. It will be seen that boot loader would then go through the operating system in from an outside storage medium such as paper tape, punched card or a disk drive.

The length of the second stage loader is that the final byte can do overwriting location 6. After the instructions in location 5 conducts, then location 6 begins the second stage loader executing. The second stage loader is seen waiting for the much longer tape which is comprised of the operating system that can be kept in t he tape reader. In the upgraded computers the bootstrapping process starts with CPU carrying out software after the reset without the interference of any outside assistance.