Saint Patrick is the Patron Saint of Ireland, and today (17th March) is St Patrick's Day.

Generally themed around the colour green and all things Irish; both Christians and non-Christians celebrate the secular version of the holiday by wearing green or orange, eating Irish foods and attending parades.

The festival is celebrated worldwide - though the largest St. Patrick's Day parade is held in New York and it is watched by over 2 million spectators.

St Patrick is traditionally associated with the Shamrock plant, which he used to explain the concept of the Trinity. He used it in his many sermons to represent how the Father, the Son, and the Holy Spirit could all exist as separate elements of the same entity. All his followers adopted the custom of wearing a shamrock on his feast day.

See the BBC's website Saint Patrick for lots more on this celebration of all things Irish.