The M-series of desktops are part of Lenovo's ThinkCentre product line. Formerly an IBM brand, Lenovo acquired the ThinkCentre desktop brand following its purchase of IBM's Personal Computing Division (PCD) in 2005. Following its acquisition of IBM's PCD, Lenovo has released M-series desktops in multiple form factors, ranging from traditional tower, to small form factor, and all-in-ones (AIOs).