Most search engines match any web page, which contains any of the keywords. One can dramatically focus the search criteria of most search engines by using it's advanced features. The vast majority of web sites receive no more than several visitors per week. While providing valuable content is important to attracting visitors, promoting the web site is also important. If one's organization's home page does not appear in a targeted search, one can easily request that it be added.
Directories often take several weeks to add a web page to it's index.
PDF files are created using the Adobe Acrobat package and read using the freely available Adobe Acrobat Reader. Acrobat Reader will automatically run when information available through the Internet is formatted as a PDF file. For instance, there could be a mailing list called croquet that's a group of croquet fans who write to each other about how much they love croquet. People use this list to communicate with others with similar interests. Distribution lists are designed for an organization to send messages to people who have subscribed to the list, e.g., people who are interested in the activities of that organization.