The fractional banking system, in a nutshell, allows banks to invest the money deposited in them, and then for whoever ends up with that invested money to deposit the money back into the bank, which can then reinvest it and so on. For example, let's say Mike puts \$1000 into a bank. The bank might invest \$800 of those dollars into a factory, which then pays the \$800 to its workers that themselves deposit their \$800 into the bank. So while Mike's bank account balance still reads \$1000, the workers' bank accounts include \$800 of those same dollars that have been paid out on loan from the bank, meaning the bank has effectively turned Mike's \$1000 into \$1800, and can loan out that same \$800 to triple dip, quadruple dip, and so on ad infinitum.
In practice, in the world and the United States, how many spendable dollars are created for each actual dollar in circulation, M0 to M1?