As popularized by modern media (ex: AC4, Pirates of the Caribbean), pirates, especially during the golden age of piracy (1650-1730), were adorned with tattoos. How accurate (if accurate, how common) is this?
The word "tattoo" comes from the Tahitian word "tatau", and the practice of sailors acquiring tattoos is thought to have been started by some of the crew of Captain Cook's first voyage (which travelled to Tahiti, and through Polynesia) in 1766.
From there, tattooing spread through the Royal Navy, became a nautical tradition, and eventually became popular in some non-nautical groups.
As this happened after the "golden age of piracy", it is unlikely that pirates adorned themselves with tattoos.
Source:
http://www.historytoday.com/tessa-dunlop/tattoos-legacy-seafaring-heritage