BY MAY next year, the public would be able to enjoy computerised services at all Urban Council libraries. The Lai Chi Kok Public Library re-opened last week to become the first of the libraries to go on-line. Hailing the achievement at the re-opening ceremony, Urban Councillor Ma Lee-wo said it was ''another milestone in the enhancement of the Council's library services''. By the May deadline, Mr Ma said Urban Council libraries ''will be the world's largest computerised public library system capable of handling both Chinese and English materials''. Users would be able to enjoy the advantage of borrowing books and other materials with a single library card and returning borrowed items to any council library. Also they could search with ease through the entire collection in any computerised library by using the on-line public access catalogues. Eventually, said Mr Ma, the computer system would allow readers to access libraries' catalogues on-line through their computers at home or at work. The council's second library to be computerised will be the Electric Road Public Library in North Point. The library's lending services will be suspended until April 12, and re-open the next day. Until then, only the counter will be open for the return of borrowed materials and for users to apply for computerised library cards.