Mobile first vs desktop first

Hi, 
The Editor of the img@srcset specification has requested that the working group clarify the differences between mobile first and desktop first. 

In particular, "Why would you need to put either mobile or desktop first?" 

People with more experience than me in this area, I would appreciate: 

1. a detailed description of both approaches.
2. explanation as to why you would choose one over the other.  
3. citations/links to authoritative sources on the matter. 

Once we refine our response, I will file it. 

Kind regards,
Marcos 

-- 
Marcos Caceres

Received on Monday, 10 December 2012 14:40:10 UTC