I have collected words and phrases used in 2channel (Ni-channel) and Nikoniko-doga，and divided them into five categories according to their characteristics: (1) grammatical，(2)phonetic，( 3) orthographical，(4 )vocabulary，and (5) style. As a result，I found that the orthographical category (inc1uding pictorial) has the greatest number of expressions，followed by the categories of vocabulary and style. In the orthographical category，there are various expressions influenced by the arrangement of Japanese letters on the key-board，the process of installing Japanese words，the similarity of letter shapes，size of letters，and omission. We find many examples of abbreviations，new words，and change of meaning in the category of vocabulary. It's especially noticeable that the words which were once deconstructed or used as parts of other words and AA (ASCII Art)，are rearranged as new words. In style，there are a lot of baby words，euphemisms，and AA，which may help to convey precisely what a writer wants to tell. Based on these analyses，I noticed that there are mainly three motives for producing new Net-words: (1)the writer's desire to differentiate their own words from other writers' words，( 2) the writer's desire to make the work easier，and/or (3) the writer's desire to create novel expressions. I think writers' desires to create novel expressions，or "word neophilia"，is potentially a rich source of new Net-words for the future."