Search engine optimization (SEO) is the process of affecting the visibility of a website or a web page in a search engine's unpaid results—often referred to as "natural," "organic," or "earned" results.
A site map is a list of all the pages on a website organized in hierarchical fashion. It also includes the relationship between those pages and any back-end functionality.
SSL / HTTPS
Similar to HTTP, HTTPS stands for HyperText Transfer Protocol over SSL (Secure Socket Layer) or, alternately, HyperText Transfer Protocol Secure. Like HTTP, it’s a set of rules for transferring hypertext requests between browsers and servers, but this time it’s done over a secure, encrypted connection.
A staging site, or a testing/best site, is the final testing platform for a site before it goes live. The site will have the full back-end system and content management tied into it and generally the final content tweaks are made here so when the site is pushed live it's 100% complete.