What is an affidavit of support or the I-864 form?

////What is an affidavit of support or the I-864 form?
In order to petition for an immigrant to become a U.S. permanent resident (receive a green card), as a U.S. citizen or permanent resident you must show an ability to support the immigrant. You must show that is not inadmissible to the U.S, as someone likely to become a public charge.  IN other words, that the immigrant will not need needs based government assistance like welfare.    An affidavit of support represents your promise to either support the immigrant financially or reimburse any government agencies from which the immigrant does claim financial assistance. You must show that you can provide the promised support and maintain the immigrant at least 125% of the U.S. government’s Poverty Guidelines levels.The Affidavit of support is done through a U.S. Citizenship and Immigration Services (USCIS) form called Form I-864.   There are two versions the short form I-864EZ and the long form I-864.  The form can also be prepared by someone who isn’t the original petition, referred to as a joint sponsor.  This is where the original petitioner’s income is inadequate and there are no household members who can contribute.