Perl CGI (Common Gateway Interface) is an early web technology that allows web servers to run Perl scripts and generate dynamic web pages. Before modern frameworks, CGI was the primary method for creating interactive websites with forms, databases, and user input processing.

When a user requests a CGI page, the web server executes the Perl script. The script processes data and outputs HTML, which the server sends back to the browser. Key characteristics include:

• Language: Written in Perl, known for strong text processing
• Environment Variables: Access to server and request data (like QUERY_STRING)
• Input/Output: Reads form data via STDIN, outputs via STDOUT with proper headers

While largely replaced by faster technologies (like PHP, Python frameworks, or Node.js), understanding Perl CGI remains valuable for:

• Maintaining legacy systems
• Learning web development history
• Simple scripts where full frameworks are unnecessary

For hosting, ensure your server supports CGI execution (often via cgi-bin directories) and has Perl installed. Though not recommended for new high-traffic sites, Perl CGI represents a foundational step in making the web interactive.