Form 8949 is used to report sales and other dispositions of capital assets. It is filed with Schedule D to list transactions for lines 1b, 2, 3, 8b, 9, and 10 of Schedule D. The form has two parts: Part I for short-term transactions and Part II for long-term transactions. The form requires you to check Box A, B, or C for short-term transactions and Box D, E, or F for long-term transactions. The form also provides instructions on how to fill out each section and what to do if the basis reported to the IRS is incorrect.