Vistaprint standard business cards are 14pt thickness (which is too thin — it feels flimsy). Premium thickness cards are 16pt and premium plus cards are 18 pt.
Paper quality is measured using two different units: points and pounds. Points are a measure of paper thickness while pounds are a measure of overall paper weight (which depends on paper thickness but also length and width and density).
When you see a paper described as 40 points (abbreviated 40 pt), that means the paper is 40 thousandths of an inch thick (0.040″). On the other hand, when you see paper described as 40 pounds, that means one ream (500 sheets) of paper weighs