The “If-Modified-Since” HTTP header is sent from an agent (browser/bot) to the web server in order to know if the requested page has been changed since its last visit. The server responds with a 200 code (Ok) if the page has been modified or with a 304 code (Not modified) if the page has not [...]

Ever had the need to see what headers a remote web site sends back to you when you request a page with your browser?

I was reading the Lynx man page the other day and I came across the –dump option. The output of: