Japanese input methods are used to input Japanese characters on a computer. There are two main methods of inputting Japanese on computers. One is via a romanized version of Japanese called rōmaji (literally "Roman character"), and the other is via keyboard keys corresponding to the Japanese kana. Some systems may also work via a graphical user interface, or GUI, where the characters are chosen by clicking on buttons or image maps. Japanese keyboards Japanese keyboards (as shown on the second image) have both hiragana and Roman letters indicated. The JIS, or Japanese Industrial Standard, keyboard layout keeps the Roman letters in the English QWERTY layout, with numbers above them. Many of the non-alphanumeric symbols are the same as on English-language keyboards, but some symbols are located in other places. The hiragana symbols are also ordered in a consistent way across different keyboards. For example, the Q, W, E, R, T, Y keys correspond to た, て, い, す, か, ん (ta, te, i, su, ka, and n) respectively when the computer is used for direct hiragana input. Input keys Since Japanese input requires switching between Roman and hiragana entry modes, and also conversion between hiragana and kanji (as discussed below), there are usually several special keys on the keyboard. This varies from computer to computer, and some OS vendors have striven to provide a consistent user interface regardless of the type of keyboard being used. On non-Japanese keyboards, option- or control- key sequences can perform all of the tasks mentioned below. On most Japanese keyboards, one key switches between Roman characters and Japanese characters. Sometimes, each mode (Roman and Japanese) may even have its own key, in order to prevent ambiguity when the user is typing quickly. There may also be a key to instruct the computer to convert the latest hiragana characters into kanji, although usually the space key serves the same purpose since Japanese writing doesn't use spaces. Some keyboards have a mode key to switch between different forms of writing. This of course would only be the case on keyboards that contain more than one set of Japanese symbols. Hiragana, katakana, halfwidth katakana, halfwidth Roman letters, and fullwidth Roman letters are some of the options. A typical Japanese character is square while Roman characters are typically variable in width. Since all Japanese characters occupy the space of a square box, it is sometimes desirable to input Roman