Sterling or Lira??

Hi Guys... Well 2 more sleeps for me and i shall be on my way on Saturday! am soo excited now and looking forward to seeing Turkey for the 1st time! 
Just a quick question i have been told that you can spend Sterling most places over there, is this the same in bars/resteraunts or just for clothes etc??. Also does it work any different (cheaper/more expensive) either way??.
Thanks for ya help, and am looking forward to arriving even more after reading all the posts on here!
Sam

Just a quick question i have been told that you can spend Sterling most places over there, is this the same in bars/resteraunts or just for clothes etc??. Also does it work any different (cheaper/more expensive) either way??.
Thanks for ya help, and am looking forward to arriving even more after reading all the posts on here!
Sam