Microsoft font here refers to the font used in the logo of Microsoft, which is an American multinational corporation, also the largest software maker in the world. Main products of Microsoft include Windows operating system, Office, Bing, Xbox etc.
Since its foundation in 1975, the Microsoft logo has undergone several changes. The longest used one (1987-2002) is the Pac-Man logo based on Helvetica Black Oblique typeface. The current logo, consisting of the tile symbol and the logotype, was introduced in 2012. The symbol of four squares in four colors is said to represent main products of the company. The logotype was designed using the Segoe UI, the same typeface used in other Microsoft products as well as their marketing. Segoe UI is supplied along with various Microsoft products like Office, Windows 7, Windows 8 etc. You can view more details about the typeface here.
An alternative to Segoe UI is Frutiger designed by Adrian Frutiger in 1975 for the Charles de Gaulle airport signage. You can view details about Frutiger here.
Download Microsoft Font
We are currently unable to find a free alternative or a font similar to the commercial font identified above, and you will need to follow the relevant links above and purchase the font.