Apache is a free and open-source cross-platform web server software.
Google Analytics is a free web analytics service that tracks and reports website traffic.
Google Tag Manager is a tag management system (TMS) that allows you to quickly and easily update measurement codes and related code fragments collectively known as tags on your website or mobile app.
OptiMonk is an on-site message toolkit used to improve conversions using action-based popups ad bars.
PHP is a general-purpose scripting language used for web development.