Apache is a free and open-source cross-platform web server software.
PHP is a general-purpose scripting language used for web development.
Progressive Web Apps (PWAs) are web apps built and enhanced with modern APIs to deliver enhanced capabilities, reliability, and installability while reaching anyone, anywhere, on any device, all with a single codebase.
Shopify is a subscription-based software that allows anyone to set up an online store and sell their products. Shopify store owners can also sell in physical locations using Shopify POS, a point-of-sale app and accompanying hardware.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.