Textboard

A textboard is a simple kind of Internet forum that does not require registration. While popular in Japan, they remain relatively unknown outside it, in contrast to imageboards (such as 4chan).

One of the key differences between textboards and traditional forums is that textboards allow users to post without registration, and often encourage anonymous discussion. The founder of 2channel, Hiroyuki Nishimura, says the philosophy behind anonymous posting is that "all information is treated equally; only an accurate argument will work." Many textboards support a form of pseudo-registration by allowing users to use tripcodes, although users tend to post anonymously.

Textboards also tend to be much simpler than traditional forums. While forums software such as phpBB or vBulletin support image or other media embedding, private messaging, polls, and various other features, textboards allow only the posting of text.

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Wikipedia