There are two types of variables in statistics as follows:
 Qualitative Variable
 Quantitative Variable
Qualitative variable: Qualitative variable also known as categorical variable is an attribute, where the characteristic being studied is non numeric. Variables will have no natural sense of ordering and are measured on a nominal scale. They can be coded to be numeric, but their numbers are meaningless. Items can be different, however the difference is not a measure.
For example, honesty, hair color, religion, profession, gender etc.,
Gender can be male or female: Male = 1, Female =2.
Quantitative variable: Quantitative variable is expressed in numerical form and arithmetic operations (add, subtract, multiply and divide) can be easily performed. Age, balance in your checking account, number of children in a family are the examples of quantitative variable. Quantitative variable can either be discrete or continuous.
Discrete variable: Discrete variable does not admit intermediate values between two specific numbers and is a whole integer value. It will have a finite number of values.Example: Number of children in a family, number of cars in a car park.
Continuous variable: Continuous variable can assume any values within a specific range and can take values between two numbers.Example: Height of 3 friends: 1.82, 1.75, 1.84.
Given below are the variable used in statistics.
Scale 
Properties

Examples
 Qualitative / Quantitative  Measure of central tendency

Nominal
Operations: =, $\neq$

There will be a difference however order will not be changed.

Santro = 1 Hyundai = 2 Volkswagen=3 Audi = 4 BMW = 5 Other = 6  Qualitative  Mode 
Ordinal
Operations: =, $\neq$, <, >

There will be a difference and direction of the difference will be indicated (less than or more than)

Food taste
Agree = 1 Strongly agree = 2 Disagree = 3 Strongly disagree = 4 Don't know = 5  Qualitative  Median 
Interval
Operations: =, $\neq$, <, >, +, 

There will be a difference and the directionality with the amount of difference in equal intervals will be indicated.

Years  Quantitative  Arithmetic Mean 
Ratio
Operations: =, $\neq$, <, >, +, , $\times$, / 
Same as interval scale with an addition of absolute zero indicated. 
Income  Quantitative  Geometric Mean 