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I am new user I just messed up some option in compiz Config Manager and it has to do with Unity. I was on CompizConfigSettings Manager menu and I clicked one of the options and whole Unity tray GONE! I also can't se Time and Date. So basically since I installed it yesterday I don't know about shortcuts in Ubuntu and how to restart it. Basically I am stuck on desktop background, it is only thing I can see.I managed to run Nautilus and access the Web browser. So If somebody can tell me how to access terminal or to restart Unity(if I only can see Dash or terminal).