The Internal Revenue Service, and your state department of taxation, have one mission: to collect taxes.  In order to accomplish this they rely on certain information being provided to them, either by your business or by other businesses, individuals and government agencies.

Business Tax Returns:  There are a wide variety of taxes assessed on, or collected by, businesses.  Corporations, and some Limited Liability Companies, may have an income tax.  Corporations which have elected Subchapter S status, partnerships and most Limited Liability Companies are known as "pass-through" entities.  This means that the tax on the business net income is paid by the individual shareholders or partners on their personal income tax returns.

Other business tax returns required to be filed with the Internal Revenue Service or your state tax department may include payroll tax returns, sales tax returns and excise tax returns.  There are also many forms, known as "information returns" which a business may be required to file.  While there may be no tax associated with these returns failing to file them may result in substantial penalties and interest.  Examples of these forms include W2 and 1099 forms.

Other Tax Returns:  There are a wide variety of other tax returns which the IRS, or your state tax department, may require you to file.  These include:

      Form 1041 (to report income for a trust or an estate)
      Form   990 (to report the activities of an exempt organization)
      Form   706 (to report the net estate of a deceased person)
      Form   709 (to report certain gifts)

If you are the trustee of a trust, or the executor of an estate, you have a legal obligation to see that the proper tax returns are filed and that any taxes due are paid.  If you fail to do so, you may be personally liable for some of these taxes.