Determine if your server can run Statamic, as well as give you some basic information about your server.
Upload check.php to your web server's document root, and then visit check.php in a web browser.
This page should tell you everything that you need to know about if you can run Statamic or not.
Note: just because your server passes the check doesn't guarantee it will run Statamic, there are always edge cases and oddly configured hosts that may throw a curve ball. Conversely, some things are hard to detect when running PHP as CGI, meaning that a failure also doesn't mean it won't run. This is just a good benchmark.