Over many years of website development, primarily based around CodeIgniter 3 and XAMPP website server configuration, a number of core elements have evolved thatmay be of interest to fellow website developers.
Registration and Logon: The capacity to identify individuals linked to an email address, with a two stage verification process, is a common feature that is based around our Registrant Class that requires the addition of relevant tables to the website MySQL database.
Captcha: Rather than feed one of the limited number of monolithic companies, that I generally judge to focus on promoting their joint and seemingly unending monetisation of the concept Tim Berners Lee is credited with "inventing", all of the websites that I maintain utilise a relatively simple challenge, requiring users to "identify" one or more universally recognised images to prove that relevant data is being orovided by a human being.
Examples of images that might be considered to have "universal" recognition comprise brand logos, football club emblems or perhaps even famous individuals. I have personally restricted my implementations to the use of brand logos, on the baiss that these represent the broadest commonly recognised elements, and whilst I have considered whether doing so breaches any restrictions that the "brand owner" might seek to enforce, I have not yet received any such objections.