ThinkPad is line of laptop computers originally sold by IBM

IBM

International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...

  but now produced by Lenovo. They are known for their boxy black design, which was modeled after a traditional Japanese lunchbox

Bento

is a single-portion takeout or home-packed meal common in Japanese cuisine. A traditional bento consists of rice, fish or meat, and one or more pickled or cooked vegetables, usually in a box-shaped container. Containers range from disposable mass produced to hand crafted lacquerware...

. Lenovo purchased IBM's personal computer business and acquired the ThinkPad brand in 2005.

Known for their reliability, quality, durability, and performance, ThinkPads are popular with large businesses and schools.