When it comes to indices, there are several ways in which an index can be formed. Globally, the most popular equity market indices are free-float market capitalization weighted. This type of index invests in individual stocks in proportion to their relative free-float market capitalization. The other most prevalent index type world over is the equal-weight index. An equal weight index follows an alternate index weighing methodology wherein the individual stocks are assigned equal weights regardless of their free-float market capitalization.