German adverbs provide more information about the nature of an action, process or condition. They refer to another word in the sentence (such as the verb) or to the sentence as a whole. Adverbs are not conjugated or inflected. 

Adverbs of location are used to describe the place or direction of something. They answer the questions "Wo?" (where?) or "Wohin?" (where to?). 

Examples:
Wo bist du? – Ich bin hier.
Wo ist der Bahnhof? – Der Bahnhof ist links. (Der Bahnhof ist rechts.)
Wohin möchten Sie? – Zum Bahnhof. Geradeaus, bitte.

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Besides place adverbs, there are also adverbs that refer to time, manner and cause or reason. They answer the questions "when?", "how?" and "why?".