RTF and DOC file formats differ from each other in various ways. A major difference is the number of features that each of the two file formats have to offer. The number of formatting options in DOC is much more than RTF. For instance, with DOC file format, a user can not only choose text formats such as bold, italic, underlined and then there is a vast variety of text fonts and sizes to choose from. In a DOC file, you have the option to present certain data in tabular or even graphical form whereas the same is not true for RTF file format.
Since the amount of data and type of data which can be stored in a DOC file is much greater and diverse than an RTF file, DOC and RTF file sizes differ from each other. Although the size of a DOC file remains considerably small no matter how much data you store in it, file size is still a difference nonetheless when comparing DOC with RTF.
Moreover, the way each file format encodes data differs as well. RTFs are encoded just like text files. This means that you do not necessarily have to use Microsoft Office Word to open an RTF file. Instead you can use any text editing software such as notepad. On the other hand, DOC file can only be opened with the proper application in which they were originally created.
The level of data security offered by RTF is practically zero whereas in a DOC file, a user has the option to encrypt data using certain encryption protocols. Moreover, a DOC file can be secured against unauthorised access by setting a password which has to be entered each time someone tries to open the file.
The development process for RTF came to a halt when Microsoft discontinued it. DOC file format however, is still being developed and new features are being added from time to time.