TIF vs TIFF
Many people are confused with similar file extensions that only differ by a single letter. One good example of this is TIF and TIFF. Well, to cut to the point, there is no difference between TIF and TIFF. They both are extensions used by the Tagged Image File Format (TIFF), which is used in storing images like photos.
The appearance of TIF and TIFF is not actually related to the format itself but to limitations imposed by file systems. A file system is basically a way of managing how data is broken up and stored in a hard drive so that it can be retrieved. Older file systems, like FAT used a naming convention called 8.3, which uses 8 characters followed by a dot, then a 3 character extension. Because it only accommodates 3 characters for the extension, it would not accommodate TIFF and the last character was omitted; and thus TIF was born. With newer file systems like NTFS, the 8.3 format has been discarded in favor of long filenames. Because of this, it has been possible to use longer extensions making it possible to use the entire TIFF in the extension.
You see TIF being used in a lot of older applications that were created prior to long filenames going mainstream. Even if you use those applications in modern operating systems like Windows 7, it would still use TIF because it has been coded into the application already. Newer programs, however, are now using the TIFF extension as it is more widely accepted; unless, of course, it detects that the file system in use doesn’t allow doing so.
In the end, there is no real difference between TIF and TIFF. Even if you renamed one to the other, you would still get the same image rendered as it should. Applications that are meant to open TIFF files are already coded to recognize both extensions and can open both with no problem at all. Even if you use the older TIF extension, all modern applications would still be able to open it.
Summary:
TIF and TIFF are the same exact thing
TIF is used in legacy file systems that use the 8.3 naming convention while TIFF is used in newer file systems that allow long filenames.