Indexing is the process where you compile an index to carry out a sequence of operations. I found their are two different types of indexing; primary and secondary. Indexing makes retrieving data much more efficient from a certain data structure. Mysql uses indexing to quickly find rows by avoiding looking through the entire data set. It allows the query to quickly determine which rows match the condition in the WHERE function. Unnecessary indexes take up space and waste time making so their must be a balance between your data and the indexes you create.