Web page is not available

I'm currently using a hp laptop with windows 8 operating system. for the past few months, my laptop was working perfectly fine. Then suddenly when I wanted to surf the Internet, they showed 'Web page is not available'. I'm using Google Chrome but I had no luck with Firefox or IE. I searched for some solutions online but none of the suggested a out ions work. I'm using LAN right now but WiFi doesn't work either. Please help me.