Why do we say ‘I’d love a cup of Joe’ when asking for coffee?

There is a whole vocabulary about coffee that we all use in everyday speech, and we hardly ever give a thought to why we say these expressions. Take ‘I’d love a cup of joe about now’ as an example:

Admittedly, most British people wouldn’t say this one, but American’s do all the time, but why?

It’s unclear where the term cup of Joe comes from but some believe that as ‘Joe’ is a common male name, you’re simply asking for a common man’s drink.

Others say it is named after a US Navy officer (nicknamed Joe) who banned alcohol on the ships in 1914. This meant the sailors drank coffee and named it after him.

Or could it be a combination of ‘Java’ and ‘Mocha’, which are two types of coffee (jamoke).