What is the difference between bootstrap and operating system?

Answer 1

Bootstrap is a process to initialise any hardware components in a device. In the case of a computer it initialises all the hardwares so that it can talk to each other and function together. While OS is used for those components to understand commands and requests made by us. so OS is kind of interpreter or a link between us and the device while BS is an internal program to initialise the components.

Bootstrap is the process where a computer, after doing whatever self initialization and testing it needs (called POST for Power On Self Test for a personal computer), somehow establishes which device it is to use. Bootstrap is also called an IPL (Initial Program Load). The device is initialized and started with a command to read an initial bootstrap program from a predetermined location as the beginning of the device:

• For a hard drive, diskette or optical media, sd card or usb flash drive it would be the first sector/track of the formatted device. On a Personal Computer hard drive, it is called the MBR (Master Boot Record)
• For a tape device, it would rewind the device and read the first block of the media.
• For a tcpip network, a computer would send out a request for an IP address and bootstrapping information. if it receives the desired response from a DHCP or BOOTP server, it will request and download a bootstrap file.

After loading (or downloading) the initial bootstrap file into memory, control is transferred to it. Its main job is download a larger amount of program code from a known or determined location, which will get more program code until the operating system is fully installed and started.

• On modern computers, determining the bootstrap device is set in the BIOS as a list of preferred devices to check in sequence.
• On some older computers, this was done by setting control panel switches to the device desired.
• On less sophisticated computers, a short program of between five and twenty actual machine instructions are toggled in to specific addresses. Starting the computer at the beginning of this program results in the IPL process being performed.