How do you work out gear ratios

Is there a difference between 48/18 and 48/17 ratio? will I be able to feel it?

Will I go faster with pink rims on a blue bike?

How can I look like a right bellend while cycling in town?

Depends what It is... and whether we let you feel it

Two slightly different shades of white are fastest

And don't cycle, sit on the handlebars and get someone to push you...