Altogether, the "Micropædia" and "Macropædia" have about 40 million words and 24,000 pictures. The index has 2,350 pages, which lists all the 228,274 topics written about in the "Britannica,". The "Britannica" uses the British spellings and not American spellings. For example, it uses "colour" (not "color"), "centre" (not "center"), and "encyclopaedia" (not "encyclopedia"). However, this rule is not always followed, for example "defense" and not "defence". The other spellings of the word is sometimes shown with a link, for example "Color: "see" Colour."