A noun is a name. This name can be that of a living thing, a place, a thing or an idea.
Example: VInod is a friendly boy. (Here, ' Vinod’ and ‘boy’ are both names of living beings)
I am standing on the road near India Gate. (Here, ‘Road’ and ‘India Gate’ are both names of places)
In order to understand this concept in detail, please visit the Grammar Section and click on the link provided for Nouns