Last "Presidents' Day" post, honest! In discussing how to punctuate Presidents' Day and when to capitalize and when not to capitalize president, I can't help but bring up another commonly-miswritten error--that of capitol and capital.
Here is the low-down, along with a trick or two to help you remember the details:
a. Means upper-case letter--most people do not use this word incorrectly here
b. Can be used as an adjective to mean primary--that was a capital idea!
c. Can be used as an adjective to describe punishable by death--capital punishment
d. A city that is the seat of the government for a state--this is where people sometimes use capitol instead
a. Refers to the building in which the U.S. Congress meets (when it is capitalized)
b. Refers to a state's main government building (when it is not capitalized)
c. Tricky Trick to Help It Stick: Only use capitol when referring to a goverment building---capitol does not have any other uses; all other uses need capital