Yarrr, 'ello me hearties. You be rememberin' today be talk like a pirate day? Don't yer forget it neither. If yer be forgettin how to talk like a pirate there be many many internets places that be explainin it for yer. Or perhaps yer be preferin' just the Wikipedia article?

'ere be a clip from the wikipedia article:

International Talk Like a Pirate Day (ITLAPD) is a parodic holiday invented in 1995 by John Baur ("Ol' Chumbucket") and Mark Summers ("Cap'n Slappy"), of the United States, who proclaimed September 19 each year as the day when everyone in the world should talk like a pirate.^[1] For example, an observer of this holiday would greet friends not with "Hello", but with "Ahoy, me hearty!" The date was selected because it was the birthday of Summers's ex-wife and consequently would be easy for him to remember.