The Gibson Martini, just like a normal Martini, is a mix of dy vermouth and gin. Instead of the using an olive to garnish the Gibson is served with an onion. 

A dirty martini is a simple cocktail using either Gin or Vodka with Dry Vermouth, olive brine and garnised with a green olive.

No one really knows where it originated from but any bond fan will remember Daniel Craig ordering his Martini "Dirty" in Casino Royale. 

Martini Cocktail serving ideas are available from Chef & Bar Supplies.  The classic 'cocktail' which probably owes much of its popularity to James Bond 'shaken not stirred'. This Gin variation is a perfect alternative for the Gin fan as opposed to the vodka martini.

Martini Cocktail serving ideas are available from Chef & Bar Supplies.  The classic 'cocktail' which probably owes much of its popularity to James Bond 'shaken not stirred'.

With so many styles and mixes the Martini world can be confusing. Classic Martinis are still popular with "Pink Gin" or "Smoky Martini" to name just two. Then there's the "you've got to try this" essential collection which includes the "Dirty Martini", "Perfect" and the "50/50". So what's the difference? Where the perfect is a mixture of both dry and sweet vermouth, plus a good quality gin, the dirty is just the dry vermouth with the choice of either gin or vodka, finished off with olive juice.