FBAR is an abbreviation for the Report of Foreign Bank and Financial Accounts. It is a report required by the US Department of Treasury from anyone who has an aggregate of $10000 or more in foreign bank accounts.
You may need to file an FBAR form if you have an interest in, or signature authority over a foreign bank account, brokerage account, mutual fund, trust of a variety of other foreign financial accounts. For those who must file an FBAR, it must be done yearly, to the Internal Revenue Service by filing Form TD F 90-22.1.
The FBAR is used to help account for discrepancies in global reporting standards by different country's financial institutions. General details are available from the IRS (on FBAR). Additional facts about FBAR for self-employed people are also available.