It is estimated that more than 50% of web sites today use Google fonts for typography. Here's a demonstration to walk you through the steps of using Google fonts and implementing the code so that your fonts load in a web site.
However, in web design you may refer to it as line-height which is the css property which controls this space between lines. Your line-height will be typically 30-50% larger than the font size you are using. In some cases, you may style it by saying it is 130% or 150% the size of the type but in other cases you may use ems to say it is 1.3 or 1.5 times the size. Just use caution not to apply excessive line-height or it may make it tougher to read the text.