Nouns

Nouns are simply the names we give to everything around us, whether it be a person, an event, a place or an object, etc. Every particular name used to define something is a noun. E.g. : Amsterdam, Anita, Blackberry, Honesty, Waiter, etc.
The names given to a group of noun to identify them as a whole are called Collective Nouns. E.g.:  pride of lions, gaggle of geese etc.
Nouns or pronouns can also modify themselves to show possession of another noun, usually by attaching 's' to the end of the noun. These nouns that show possession are called Possessive Nouns.
Sometimes nouns have different forms for different genders, although this practice has been largely abandoned by the people who prefer to use the same noun for both genders. For example - Actor (male) - Actress (female), but people nowadays refer to women who act as female actors rather than actresses.
Most nouns can be converted into plural forms by adding ‘-s’ or ‘-es’ at the end of the word. E.g.:  box-boxes, cat-cats, echo-echoes , etc.
But some nouns require the last consonant to be modified before adding ‘-es’. For e.g.: the ‘Y’ in ‘city’ changes to ‘I’ to form  cities, kitty to kitties and ‘f’ to ‘v’ in  dwarf to dwarves, wharf to wharves, etc.
Some nouns become plurals irregularly by changing the entire word: mouse- mice, ox - oxen, etc.
You can learn more about Plurals here: How to make Plurals : Making Plurals-Easy Guide

Grammarians have divided nouns into different categories based on their use and purpose. Learning these divisions within the nouns will help in sentence construction and vocabulary.  The different types of Nouns are -

PROPER NOUNS
These nouns are the names of specific people and places. These nouns also refer to the names of the days of weeks and months, and also the various names for religions, organizations, institutions, etc. Proper nouns basically refer to the names that are specific to that particular noun.  These nouns are always capitalised as they need to be distinct from other nouns.

• William Shakespeare was a playwright. - Proper noun that is the name of a specific person.
• I will be visiting New York next month. - Proper noun that is the name of a specific place.
• Everyone dislikes Monday mornings. - The names of days are proper nouns. 
• The holy book of Islam is the Koran. - Name of a religion and religious text.

COMMON NOUNS
These are the nouns that are used to denote a general category of people, places or things. They are capitalized only when they are at the beginning of a sentence. Common Nouns don’t refer to something specific rather they are a general term used for every noun of a particular kind or type.

• The boys went to play cricket. - Both boys and cricket are common nouns as they can refer to any boy or any cricket match. There is nothing specified by these nouns.
• This neighbourhood is one of the best in the area. - Here neighbourhood is the common noun as there are innumerable neighbourhoods all over the world.
• She was trying to answer her phone while buying coffee. - Here we see phone and coffee that both are general indicators of the object and the drink. 

ABSTRACT NOUNS
These nouns are the names of things that we cannot perceive through our five senses of touching, smelling, seeing, hearing and tasting. These nouns can also refer to medical conditions related to the mind and are also used to express  thoughts.

• She screamed with great delight. - Delight is an abstract noun as it tells about the state of a person’s mind and any actual physical thing. 
• His bravery in the war won him a medal. - The abstract noun bravery is used to name the motivation behind certain actions made by people.
• One should learn to be as independent as possible. – Here, independent describes a state or a way of being, hence it is an abstract noun.

COUNTABLE NOUNS
The nouns that fall under this category are the ones that have both singular and plural forms. They can be counted either relatively or completely, and form plurals to associate with plural verbs in a sentence. They can also be expressed in numerical terms

• I need to buy four new suitcases for my trip.  - Suitcase (s) is a countable noun as adding ‘s’ to it makes it plural.
• Does anyone want some oranges? - Here some is being used to count the noun orange(s).
• She had a pet dog. - Dog is also a countable noun as its plural is dogs.

UNCOUNTABLE NOUNS
These nouns are the exact opposite of Countable Nouns. These nouns are the names of things that cannot be counted and have only a singular form. These nouns use singular verbs in a sentence.

• The furniture was damaged in moving out. - Furniture is an uncountable noun and therefore, we use the singular ‘was’ in referring to it.
• Is 250gms of sugar enough? -  Here, sugar is an uncountable noun as sugar itself cannot be counted. It can only be weighed. 
• He always answers questions with honesty. - Honesty is an uncountable noun as it has no plural and cannot be counted in physical terms either.

Sumber :
http://www.englishleap.com/grammar/nouns