A more thorough explanation:

Definition: An index is an alphabetical list of topics or items included in a book, document, or series of volumes. It is usually found at the end of the book or document. An index can also be a number that measures a series of observations, especially those involving a market or the economy.

• Grantee-grantor index: This is an index that is kept in the county recorder's office. It lists the recorded property transactions alphabetically by grantee or grantor. For example, if John Smith sells a property to Jane Doe, the grantee-grantor index will list the transaction under Jane Doe's name.
• Cost-of-living index: This is a number that measures the changes in the cost of goods and services over time. It is used to calculate the amount of money needed to maintain a certain standard of living. For example, if the cost-of-living index is 120, it means that it costs 20% more to maintain the same standard of living as compared to the base year.
• Stock index: This is a number that measures the performance of a group of stocks in a particular market. It is used to track the overall performance of the stock market. For example, the S&P 500 is a stock index that tracks the performance of 500 large-cap stocks listed on the US stock exchanges.

These examples illustrate how an index can be used to organize information or measure performance. The grantee-grantor index helps to keep track of property transactions, while the cost-of-living index and stock index help to measure changes in the economy and stock market, respectively.