The majority of topics were requests for information such as instrument comparisons, interpretation of spectra, advice on instrument or software problems, and suggestions of procedures to accomplish a task. One of the goals of the newsgroup was to provide a place for users to ask questions and receive prompt replies. The achievement of this goal is shown in Figure 3 . Users have also received private responses via electronic mail, which increases the total number of responses. Responses are usually received within a day or two, showing that the newsgroup is a timely source of information.
Responses are also independent of time zones.
A user may ask a question at the end of the day, and return the next morning to see an answer from someone halfway around the world. In addition, a user does not need to be able to read Usenet newsgroups directly to take part in discussions. Anyone with an electronic mail address can submit articles for posting, and can receive a summary of postings on a regular basis. This gives the newsgroup world-wide coverage, with a wider impact than journals or conferences. A news reader program keeps a list of the newsgroups carried at its site, and records which groups each user is subscribed to.