Authorize.net is a secure online payment gateway service that enables businesses to accept payments through various channels, such as ecommerce websites, mobile devices, and retail stores, providing a trusted platform for processing credit card and electronic cheque payments.
Websites that have a shopping cart or checkout page, either using a known ecommerce platform or a custom solution.
Facebook pixel is an analytics tool that allows you to measure the effectiveness of your advertising.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Javascript forms validation script.