The 1918 flu pandemic, commonly referred to as the Spanish flu, was a category 5 influenza pandemic caused by an unusually severe and deadly Influenza A virus strain of subtype H1N1.
Project Lead The Way (PLTW) is an American nonprofit organization that develops STEM curricula for use by US elementary, middle, and high schools.
btw in British English. See all translations. btw. âº written abbreviation for by the way: used, for example in emails, when you are writing something that relates to the subject you are discussing, but is not the main point of the discussion: I hope you enjoyed your holiday in Florida - btw, can you recommend a good hotel?