Form 990 is a tax form required by the United States Internal Revenue Service (IRS) that provides the public with financial information about a nonprofit organization. It is also used by government agencies to prevent organizations from abusing their tax-exempt status. The form is officially called the "Return of Organization Exempt From Income Tax". Here are some key points about Form 990:

• The form is used to give the IRS an overview of the organizations activities, governance, and detailed financial information.
• The form is designed to increase financial transparency and includes revenue, expenditure, and income data in addition to information used to justify maintaining the organizations tax-exempt status.
• Most tax-exempt organizations must file Form 990 annually, including 501(c)(3) tax-exempt charitable and nonprofit organizations.
• There are several versions of Form 990, including Form 990-EZ ("Short Form Return of Organization Exempt From Income Tax") and Form 990-N ("e-Postcard") .
• Form 990 can be filed with the IRS by mail or electronically with an authorized IRS e-file provider.
• The form is a public document that can be searched for on the websites for the Secretary of State or the Attorney General where the organization is incorporated.

In summary, Form 990 is a tax form required by the IRS that provides financial information about a nonprofit organization to the public and government agencies. It is used to increase financial transparency and ensure that organizations continue to qualify for tax exemption after the status is granted.