Ahrefs is an online toolset utilised for search engine optimisation (SEO) and competitor analysis, which permits users to analyse their website's performance, track keyword rankings, identify backlink opportunities, and research competitors' websites, among other features.
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.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Quantcast Measure is an audience insights and analytics tool.