Noch most directly has the meaning of still. As such, it has basically for types of usage. The temporal usage of the word. (as it relates to time) can be seen in these examples. Es regnet noch. Ich bin noch nicht fertig. Er hat noch etwas zu erledigen. Ich wünsche dir einen schönen Tag noch. It is still raining. I am still not finished. He still has to take care of something. I wish you a nice day still.
The marginal usage of the word. (as it relates to place) can be seen in these examples. Die Stadt Coburg liegt noch in Nordbayern. Das liegt noch in Georgia oder? Die Buchhandlung befindet sich noch in Berlin. The city of Coburg is still in Northern bavaria. That is still in Georgia, or? The book store is still located in Berlin.
The additive usage of the word. (as it relates to additions) can be seen in these examples. Ich hätte noch ein Bier bitte. Kann ich noch ein Glas Wasser haben? Du musst noch mehr studieren. I would like to have another beer please. Can I have another glass of water? You must study still more.
The comparative usage of the word. (as it relates to comparing different things) can be seen in these examples. It often has the meaning of even in these cases. Das Auto ist noch schneller. Meike ist noch intelligenter als ich. Es wird noch schlechter. The car is even faster. Meike is even more intelligent than I. It gets even worse.