The total number of shares of stock that a company has issued for public trading or has at a moment available for the trading public. In calculation, float is figured out by subtracting restricted shares from total outstanding shares:

Float = outstanding shares – restricted shares

Restricted shares are unregistered, non-transferable shares an entity issues for its staff and employees, as an incentive and an alternative way of motivation (bonus, etc.) These shares represent an equity stake in an entity, and are restricted- i.e., cannot be disposed of or transferred to a third party, subject to a vesting plan.