LIKERT SCALE
The Likert Scale is the most commonly used scale in quantitative research.
The original version of the scale included 5 response categories, and each response category was assigned a value.
Usually, the most negative response is given a numerical value of 1, whilst the most positive response has a numerical value of 5.
Obviously you can work out that the point in the middle would have a numerical value of 3.
Response choices in a Likert Scale usually address:
Example
of a Likert Scale:
Statement: This method of teaching you about quantitative research methodology is useful. Likert Scale:

However, do take note that the use of the 'uncertain' or a 'neutral' category is controversial because it allows the subject to avoid making a clear choice of positive or negative statements.
Consequently, sometimes only four or six options are given, and when this happens, it is known as a forced choice Likert Scale.