Browser User Agents

One of the most comprehensive sites listing User Agent strings for Browsers, Robots and Spiders is at the following link. This site can be searched for matches but the basic layout is a table listing entries categorized by the first letter of the User Agent. The list is split into parts accessed by the links A-F, G-L, M, N-S and T-Z. The A-Z link includes additions and those User Agents not starting with an alphabetic character:

  Psychedelix (Be careful. See the note below)

The above site was developed by Andreas Staeding and these links, Link1 and Link2, will search Google for matches, just in case you want to check whether the site has suffered from problems.

Spiders and Robots can be excluded from your site if you have a robots.txt file, but this won't deter those who seek email addresses and other information for the purposes of spam. If you need to know more about the exclusion of robots from your site, see the following link:

  The Web Robots pages (Be careful. See the note below)

The above site was developed by Martin Koster and this link will search Google for matches, just in case you want to check whether the site has suffered from problems.

Note: The safety of arbitrary links on a web page cannot be guaranteed. Ensure that the Internet Zone of your browser has Active Scripting (i.e. Javascript) disabled. This prevents a good proportion of potential security breaches.
Why does Note above have a link? If the page grows in future, clicking that link will scroll the page down to the word Note which is an anchor tag with a Name attribute.