What were the two speakers talking about?

W: How many holidays do you have in the U.S.?
M: Er, I’m not quite sure. I just know some.
W: For example?
M: Mmm..., Mother’s Day, National Day, Thanksgiving Day, Christmas Day, New Year’s Day, and Valentine’s Day.
W: Not bad. When does its National Day come? And the Valentine’s Day?
M: The National Day comes on July 4th and the latter on February 14th.
W: Talking of the National Day, who is the Father of the state? Benjamin Franklin or George Washington?
M: George Washington, of course.
W: Besides Washington, who else is regarded as a great president?
M: Abraham Lincoln, I’m one hundred per cent sure.