What is line-height:1?
css
Solution
Possible Values
number :
Sets a number that will be multiplied with the current font-size to set the distance between the lines
length :
Sets a fixed distance between the lines
% :
Sets a distance between the lines in % of the current font size
take from http://www.w3schools.com/css/pr_dim_line-height.asp
Problem
It is a question about the appointment of line-height. I began study of css. line-height: Examples appointing 20px or a unit are often found. It is sometimes line-height: There are 1 and a thing without a unit, but what kind of meaning does this become?