There’s a lot of confusion about the popular PDF readers and editors Adobe Acrobat and Adobe Acrobat Reader, especially since the two products have been changing names. So, to be clear:

• Adobe Acrobat Reader DC is the newest version of the free Adobe suite. You can download and use this program to view PDF documents and comment on them (if they are review-enabled). The program was formerly called Adobe Reader. You can add additional functions to the Reader, depending on which ones you want to use.

  By default, the Reader comes installed with free adware. During installation, don’t forget to turn these optional downloads off.

• Adobe Acrobat is the full, paid, version of Acrobat. Sometimes the program is called the Adobe Viewer as a non-official name.
  At this time, Adobe has 2 versions of Acrobat:
  • Adobe Acrobat Standard DC
  • Adobe Acrobat Pro DC

See also The Adobe Acrobat family on Adobe.com