Anything that can be counted, whether singular – a dog, a house, a friend, etc. or plural – a few books, lots of oranges, etc. is a countable noun.
EXAMPLES
There are at least twenty Italian restaurants in Little Italy.
Megan took a lot of photographs when she went to the Grand Canyon.
Your book is on the kitchen table.
SUMMARY
In my personal opinion, the countable noun is everything that can be counted or numbered.
Anything that cannot be counted is an uncountable noun. Even though uncountable nouns are not individual objects, they are always singular and one must always use singular verbs in conjunction with uncountable nouns.
EXAMPLES
There is no more water in the pond.
Please help yourself to some cheese.
I need to find information about Pulitzer Prize winners.
SUMMARY
An uncountable noun is
everything that cannot be counted or numbered because it is very numerous.