October was a busy month for mergers and acquisitions. The highlights include the largest technology acquisition in history, with Dell buying EMC (EMC)Walgreens Boots Alliance (WBA 0.51%) and Rite Aid (RAD 25.00%) combining to form a drugstore behemoth, and Western Digital (WDC -0.61%) taking out SanDisk (NASDAQ: SNDK).

Click through the following slideshow to see an overview of five of the most important acquisitions that took place in October, including Pandora's (P) entry into online ticket sales and the combination of snack-food companies Snyder's-Lance (LNCE) and Diamond Foods (DMND.DL).