minecraft isn't working

Why isn't Minecraft working???? I tried Minecraft on my macbook first, then I tried in on the IMac. Neither of them worked! Then i called my friend on Skype. The same thing happened to him. We kept getting the error, "Can't connect to Minecraft.net." It would only let me play it offline. I knew that you could delete your bin folder, and it would refresh Minecrafts memory and get rid of mods. That made it worse. I couldn't even play offline!!!!!!! D: What should I do!?!?!?!?!?!?!?