Apache is a free and open-source cross-platform web server software.
Buy me a coffee is a service for online content creators that they may use to receive tips and donations to support their work.
Donorbox is a US-based technology company. It offers an online fundraising software that allows individuals and nonprofit organisations to receive donations over the Internet.
Open Graph is a protocol that is used to integrate any web page into the social graph.
PayPal is an online payments system that supports online money transfers and serves as an electronic alternative to traditional paper methods like checks and money orders.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.