The Greek letter π is the symbol for the irrational number representing the ratio of the circumference of a circle to its diameter. It is approximately 3.1415926. Pi Day is an annual celebration on March 14th (3/14), with this year’s being a very special Pi Day (3/14/15).
The National Institutes of Health will celebrate Pi Day 2015 with a series of events on Pi Day Eve (March 13, 2015) to promote data science, which combines statistics, computer science, and the biological sciences. Alex Szalay of Johns Hopkins University has described data scientists as "pi-shaped," with both a wide breadth of knowledge and a depth of knowledge in both biological science and statistical and computational methods, unlike the traditional "T-shaped" researcher, who have deep skills and knowledge in a very specific area.
Pi Day at NIH is hosted by the Office of the Associate Director for Data Science, the National Institutes of Health Library, and the Office of Intramural Research. Additional support is provided by the Foundation for Advanced Education in the Sciences (FAES).