Calcium is written in Perl, so it will run without modification nearly anywhere - including on remotely hosted web sites. This includes just about any kind of server running unix, Linux, Microsoft Windows, Apple OS X, and other systems as well. The only system software you'll need to get Calcium handling your calendrical needs:

• Perl, version 5.004 or better.
• any HTTP (web) server that can handle CGI scripts; Apache is an excellent choice, and like Perl, it's free.

Notes:

• Microsoft Windows: Perl is available for free from ActiveState. You'll also need web server software, like IIS from Microsoft, or Apache, which is freely available from the Apache Software Foundation.
• Apple Macintosh: all versions of OS X come with Perl and Apache, you don't need anything else. (The Calcium server will not run on OS 9, but calendar users can browse from any platform.)
• Apache: Calcium runs fine (and fast) under mod_perl/Apache::Registry. Here is more information.

Setting Calcium up on your system is very easy, since it runs as a plain CGI script under control of your web server. This means it works on remotely hosted web sites too - no changes to the web server configuration or special access is required, simple FTP is all that's needed.

Installation is simple - just unpackage the distribution in your web server's cgi-bin directory. Or, download the single, small installation script, put in your cgi-bin directory, and browse to it; it will do the rest! This makes it quite easy to install on most web sites, even remotely hosted ones.

Or, if you have direct access to the server, you can use a platform specific installation package; available for Microsoft Windows, Apple OS X, and linux RPM.

Finally, once it's installed you don't have to access the web server's file system again. You can do everything with a web browser, including administrative tasks such as changing the look of calendars, managing users, and creating new calendars.