Well, you certainly can do this with HTML. An example of this is this forum. Basically, you would use some scripting to substitute one value for another.
For example when you click on one of the Smilies on the left [ :) ], it inserts a certain character string into the textbox. When it is read from the database, it replaces it with the corresponding image. :D.
That being said, there are certainly several applications for sale that do this for you and you would have to determine if it is worth your time to develop it or just pay for it.