How Many Names Did The Mark Twain Adopted As His Pen Name Before Deciding For The Final One?

It is a very interesting question. American famous and great writer whose real name was Samuel Clemens used many pen names before adopting a final pen name as Mark Twain.
Before using Mark Twain as his permanent pen name he first of all used the pen name "Josh" with which he signed different humorous and imaginative sketches until the year 1893.

He also used another pen name in writing different kind of humorous letters and that name was "Thomas Jefferson Snodgrass". He used this pen name for a series of humorous letters which he had written.

At last he came to the point of using the pen name "Mark Twain" and from this pen name he got popularity among his readers and in people. He maintained that he took this name while he was studying the Mississippi river and working on Mississippi riverboats. Samuel was working on the riverboat with the boatman for measuring the Mississippi river with the boatman and they were in river at that time. The boatman cried telling him that the mark is safe for water and his actual words were "mark twain" where the twain means two in archaic term. Hence from here Samuel Clemens adopted his permanent pen name as Mark Twain.