Toolmenu in the TextBox where you write these posts

I am creating a forum and now I have come to the point where I will create the textBox where you writes your post. Like when you are writing a post here, you can see that there is lika tools menu.
 
* What I wonder for is perheps the whole field, if that is a standard for ASP.net webpage ?
* For now I am thinking of saving the posts as ordinary .txt files but what will happen with for example a smiley as: and bold strings like: BoldString. ?
* Will these just be saved as codetags <b></b> etc... and by any feature or property for the textBox, they will be converted automatically when the lines is inserted in the textBox or other control ?
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