1. A character input method, comprising the steps of: when a user brings a mouse cursor ( 30 ) into contact with a term input box of a web browser ( 10 ) or website, or clicks the term input box one or more times, displaying a character input window ( 100 ), in which two or more character buttons ( 110 ) and a completion button ( 120 ) for enabling input of a signal indicative of completion of entry of one or more characters are arranged, in abutment with the term input box; when one or more of the character buttons ( 110 ) are clicked, entering one or more characters corresponding to the clicked character buttons ( 110 ) into the term input box; and when the completion button ( 120 ) is clicked, generating an activation signal so that an search engine associated with the term input box is run using the characters, entered into the term input box, as search data.