It was, and worked well with rtf. I vaguely recall it being better than notepad if you were for example looking at strings in binary files, something like that, I forget...
I often used it to convert unix style line endings to windows. Notepad choked on those, wordpad could load them easily, and just resaving them as a txt file converted them to windows line endings.
IIRC Wordpad was the only always-installed program which could open text files with Unix line endings and display them properly. Until at least Vista, Notepad would treat them as if containing a single line.