N is Natural Numbers
These are whole positive numbers such as 1,2,3 etc,
To graph this place a dot ( .) above the number
Z is Intergers
These are whole positive and negative numbers, such as -1, 1 etc
To graph this place a dot above the number
R is Real Numbers
These are any type of number, positive, negative, decimals etc
To graph this, draw a small circle (o) above the number and draw an arrow in the direction of the inequality
Eg <4 means x is smaller then 4, so draw an arrow in the left

Alex F— 30/10/16