Number is new input type introduced with HTML5. This type can be used when you want to allow the user to add only numeric value is the input field. There are number of addition option attributes that will allow to add extra restriction on the user input.
The default value of the input field is the number supplied in the value attribute, Will allow only numeric value. Field has slider associated with it which is used to increase or decrease the value. Value will increase or decrease by the amount equal to stepvalue.
Note: Browser not supporting type=number will render it asnormal text input field. So you can start using the same in place where yourequired to have field that allow only numeric value.