Click-through rate (CTR) is the number of users who click on a specific link out of the total users who view a page, email, or advertisement.mail click-through rate is expressed as a percentage, and calculated by dividing the number of click throughs by the number of tracked messages delivered. Most email marketers use this metrics along with open rate, bounce rate and other metrics, to understand the effectiveness and success of their email campaign.
Moonbat is a pejorative political epithet used in United States politics, referring to liberals, progressives, or leftists.
Descriptions of bat-like people on the Moon were part of the 1835 Great Moon Hoax. A long poem The Proving of Gennad: A Mythological Romance by Landred Lewis (1890) uses the term moonbat to refer to unsound ideas, but not specifically political ones.