Hosts file is missded every thing up

Hello , HOW should HOSTS file looks like ???

cauz am having a serious problem , where , i cant connect to localhost , phpmyadmin ,
they are working but on the browser they are not showing any thing except unable to connect ,
but pinging localhist or is sending requests ,

so am gussing the problem in hosts file . please help me , all my work is on hold now ,
thanks in advance