This aphorism refers to the act of helping yourself with little to no outside assistance or influence.
This term's origins lies in the 17th century, when people who had fallen down would literally grab a hold of their bootstraps (presumably a sturdier precursoer to shoelaces) and use them to sit upright.
During the earliest days of computers, it was decided that the best way to have a computer run would be to have initial, low level machine language code that would initiate more complex code using a memory reference; this code would in turn call more code, and so on and so forth until all of the code to operate the computer had been loaded. (Today, we have a somewhat similar system in our BIOS and autoexec.bat file.) This process was named bootstrapping - later shortened to "booting."
Perhaps the most famous "bootstrapper" is Michael Dell, who started Dell Computers out of his parent's garage.
The phrase may also refer to someone who works hard and ascends through seniority or competence, rather than a "young hotshot" or someone who unfairly attains success in the business world.
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