As vs like

As  - conjunction
Like - preposition


Bob acted like my brother.
Bob acted as I would expect my brother to behave. 
As I was saying...
As grandma used to make them
As in America

Always in past subjunctive:
It seemed as if he were running out of puff.
My neighbour yelled as though he had seen a banshee.

National regulatory authorities like (such as) Ofcom and Arcep

Source: http://www.quickanddirtytips.com/education/grammar/like-versus-as
http://www.economist.com/style-guide/like-unlike 
http://dictionary.cambridge.org/grammar/british-grammar/as-or-like 
http://www.grammar.cl/Notes/Like_vs_As.htm

Squiggly throws like a raccoon or Aardvark acted just like my brother. - See more at: http://www.quickanddirtytips.com/education/grammar/like-versus-as#sthash.5VFqgj9w.dpuf

use like when no verb follows

use like when no verb follows

use like when no verb follows

Key

Do not use as a free-standing adjective (The choice of running-mate is key)


Source: http://www.economist.com/style-guide/key