A time-based currency, or TimeBank, allows people to exchange their time and skills for another persons time and skills.
Like to a mutual-credit currency, a TimeBank can consist of a ledger that records the time each member has contributed, and to who, establishing each members positive or negative balance. A TimeBank can also include a directory of services that members are offering and seeking.
TImebanking allows for specialization while avoiding some of the problems of other money systems.
Generally everyone's time is valued equally in a time-based currency which contributes strongly to economic equality and is uncommon when other types of currency are used.
Time based currencies robustly decentralize and solve the issue of how, and by whom, the 'supply' of the currency is issued.