Knowledge is often considered synonymous with terms like familiarity, understanding, wisdom, education, awareness, etc. Knowledge can be expressed in the form of data, scientific formulae, product specifications, manuals, universal principles, and so forth.There are two broad categories, conceptual knowledge, and procedural knowledge, in which we can divide mathematical knowledge. In order to make sense of these categories, we need to understand concepts and use of procedures, or algorithms that we come across as we do mathematics.Procedural knowledge: We need procedural knowledge for making use of concepts. It relates to knowing the procedure for doing a certain task.For example, when we add 2 two-digit numbers, we must start from the units column; carryover if the total is more than 9; then add the second column; finally use the hundreds column in case the total exceeds 9.For being able to learn this task first of all we need to observe that steps need to be carried out in the order they have been specified. However, for remembering the steps it is necessary that the learner understands the logic behind each step and the concept behind that step.For example, if the learner is not comfortable with the concept of place value, she will find it difficult to appreciate the importance of the step of carrying."What is the method of adding 3 - digit numbers?" - is related to procedural knowledge as the student can describe the method of addition of 3 digit numbers only if, he knows the procedure and steps of how to do that sum.example: 213 +423 636Hence, we can conclude that "What is the method of adding 3 - digit numbers?" - is related to procedural knowledge.Additional InformationConceptual knowledge relates to the formation and development of concepts (abstract ideas) in the mind of the learner. Concepts are results of observation of different situations which allow us to recognize patterns (underlying similarities) in those situations.