For online internet marketing CTR holds a good responsibility for advertisers and publishers. For generating money CTR plays an important role.
Click Through Rate is nothing but number of times an advertisement is clicked divided by number of time page advertisement is viewed.
So it is the percentage of number of clicks on advertisement and number of time page advertisement is viewed.
CTR = Number of clicks / Number of exposures
CTR% = Number of clicks * 100 / Ad Impressions
For a simple calculation if you have an ad on your webpage and it is seen by 100 people and only 10 users clicked this then CTR is 10%.
To maintain better CTR of a advertisement you can see the article “Google Adsense makes you earn $100 a day and you do not know how much traffic you need“.