When sending or receiving a file, a format is imposed on the file. You have to select the format when asking to send or receive the file.
The two usual formats are Text and MacBinary. Text means straight ASCII text, or what is called on the Mac a "text only" document. Word processor file formats are not considered text in this sense. Text format is only allowed in a Send if the file is in fact straight text; however, since TOPS Terminal can't tell what format applies to files stored on another computer, it is possible to try to Receive a non-text file in text format.
MacBinary format should be used for all kinds of Mac files which are not text only. It concatenates all parts of a Mac file into a single stream of data understandable by other computers as a single file. It is described fully in its own entry.
There are two obscure transfer types, Data and Resource, usually used only by experts. Data format means to use only the data fork of the file, while Resource format means use only the resource fork.
Data format would be useful if you had a binary document (that is, not text) on another computer which was not a MacBinary file, but a word processor document, graphics document, or some other binary format. If you wanted to get a copy of the file on the Mac for some reason, you would specify Data format.
Resource mode is not useful to most people; if you would have any need for it, you probably can figure out how to use it. In general, it would be used in conjunction with the "Set File" desk accessory to restore the file's owner, creator, and possibly bundle bit.
