Title Tags & Meta Descriptions
These are bits of HTML code in the header of a webpage. They help the search engines understand the content on a page. They are also shown whenever a page appears in search engine results. They serve as a hook to draw readers to a website from the SERP.
Open Graph
Open Graph is an internet protocol created by Facebook to standardize the use of metadata within a webpage to represent the content of a page.
When implemented correctly, they allow for a rich preview of the content on a webpage when shared on social media platforms.
Alt-text
Alt-text is the written copy that appears in place of an image if the image fails to load on a user's screen. This text also helps screen-reading tools describe images to visually impaired readers, increasing accessibility.