What is the difference between a short form report and the URAR?

What is the difference between a short form report and the more commonly used and traditional Fannie Mae/Freddie Mac (URAR)?

The URAR report is relied on primarily by the primary and secondary mortgage lending market. It contains many items and requirements that are not necessarily required in order to estimate value. Both reports rely primarily on direct sales comparison (market approach) with a market grid to determine the value of the subject property. Short form reports are well suited for tax appeal, gift and estate tax purposes, helping a seller price a home, assisting a buyer in determining what price to offer or pay for a home, uncontested divorce proceedings and most any other potential use other than for obtaining a mortgage or in litigation where the report will be used in conjunction with expert testimony.