Website using the £ symbol on their website - meaning it may accept payment in this British currency.
Content Security Policy is best used as defense-in-depth, to reduce the harm caused by content injection attacks.
The http-equiv attribute provides an HTTP header for the information/value of the content attribute. The http-equiv attribute can be used to simulate an HTTP response header.
When running in a browser on a mobile phone, "format-detection" meta tag determines whether or not telephone numbers in the HTML content will appear as hypertext links. The user can click a link with a telephone number to initiate a phone call to that phone number.