Why doesn Google offer its own public domain name server?”
I don’t work for google, so whatever view is offered is that of an observer. * In my opinion, Google is a company made by computer scientists who think of an engineering product first, and then build a business model around it (unlike Microsoft which goes the other way). * Google perfects its engineering product because that’s what their core model is. Example: Google search was perfected before ads appeared there. Gmail was perfected in early release before showing ads. Google earth etc are still Ad-Free. * Since google believes in engineering product, a typo like DNS service (which is just a gimmick) is not of interest to them. Money lies in selling coca-cola too, just like money lies in showing DNS service ads. But Google may not be doing either of these, since they are outside the scope of their engineering. A lot of time, it makes sense to stick to one family of product and excel in it. Adobe, Google, Apple, Amazon, etc are burning examples of this. Running to too many families an