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.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Open Graph is a protocol that is used to integrate any web page into the social graph.
OpenResty is a web platform based on nginx which can run Lua scripts using its LuaJIT engine.