What is the definition of Stock-Based Compensation (SBC)?

The best way to see this is, some company can pay you in stocks instead of cash. 

By definition, A Stock-Based Compensation (SBC) is a way of paying employees without paying them cash. Frequently, SBC will allow employees to purchase a given number of shares at a given price. Once the company's shares surpass that "vesting price," the employee is compensated by the difference in the current share price and the stock options strike price. Depending on what the stock option (vesting price) is, this helps companies align their interests with that of their employees.

SBC is commonly used by start-ups and IT firms to entice employees without having to lay out large sums of cash that the company may not have or want to use to pay employees.