The pandas provides many built-in indexes. Each of the index types is designed for optimized lookups based upon a specific data type or pattern of data. Let's look at several of them that are common used.

This type of index is the most generic and represents an ordered and sliceable set of values. The values that it contains must be hashable Python objects. This is because the index will use this hash to form an efficient lookup of values associated with the value of that object. While hash lookup is preferred over linear lookup, there are other types of indexes that can be further optimized.

It is common that the columns index will be of this generic type. The following...