The word "value" has already been used in this book, but what does it really mean? When a valuer uses the word it will normally mean "market value", which can be defined as the "money obtainable from a person or persons willing and able to purchase an article when it is offered for sale by a willing seller". There is no compulsion on either the vendor or the purchaser to enter into a transaction. The vendor will only sell if he or she obtains the sum required and the purchaser will only buy if he or she can do so at what is considered to be a satisfactory price. They are both willing parties to the transaction because they both consider the deal to be to their own personal advantage. The expression "market value" can be defined in many different ways, but the important thing is to grasp the concept rather than to remember any particular form of words.