A translation system comprising: a translation request receiving unit for receiving, from a web server or a user terminal, a translation request including a Universal Resource Locator, URL, of a web page in which text in a first language is displayed; a translating unit for translating the text in the first language included in the web page indicated by the URL into text in a second language by referring to a bilingual database storing words and phrases in the first language associated with words and phrases in the second language constituting translated text of the words and phrases in the first language; a translation sending unit for sending the translated text in the second language to the web server or the user terminal; an untranslated text receiving unit for receiving, from the user terminal, untranslated text in the first language included in the web page translated into the second language, the untranslated text being detected by a script embedded in the web page executed on the user terminal on the web page updated dynamically; and a translation updating unit for associating a word or phrase in the first language corresponding to the untranslated text with a word or phrase in the second language constituting a translation of the word or phrase in the first language and registering the association in the bilingual database; wherein URLs are included in the bilingual database, the URLs associating words and phrases in the first language with words and phrases in the second language, thereby to customize translations for the URLs included in the bilingual database; and the translating unit is for translating text in the first language into text in the second language based on the words and phrases in the first language and the words and phrases in the second language associated in the bilingual database by the URL included in the translation request. a translation request receiving unit for receiving, from a web server or a user terminal, a translation request including a Universal Resource Locator, URL, of a web page in which text in a first language is displayed; a translating unit for translating the text in the first language included in the web page indicated by the URL into text in a second language by referring to a bilingual database storing words and phrases in the first language associated with words and phrases in the second language constituting translated text of the words and phrases in the first language; a translation sending unit for sending the translated text in the second language to the web server or the user terminal; an untranslated text receiving unit for receiving, from the user terminal, untranslated text in the first language included in the web page translated into the second language, the untranslated text being detected by a script embedded in the web page executed on the user terminal on the web page updated dynamically; and a translation updating unit for associating a word or phrase in the first language corresponding to the untranslated text with a word or phrase in the second language constituting a translation of the word or phrase in the first language and registering the association in the bilingual database; wherein URLs are included in the bilingual database, the URLs associating words and phrases in the first language with words and phrases in the second language, thereby to customize translations for the URLs included in the bilingual database; and the translating unit is for translating text in the first language into text in the second language based on the words and phrases in the first language and the words and phrases in the second language associated in the bilingual database by the URL included in the translation request.