Microsoft

Microsoft Corporation (NASDAQ: MSFT), which went public in 1986, is arguably one of the most profitable American businesses in U.S. history. In 1975, childhood friends Bill Gates and Paul Allen converted BASIC, a programming language, for use on a personal computer. Within five years, Microsoft won an IBM contract to create an operating system, MS-DOS, for its groundbreaking personal computer. By 1990, Microsoft sold more than 100 million copies of MS-DOS worldwide.

The company's success made Bill Gates the richest man in the world for a long time though he continues to remain the second-richest today. The company itself commands a market capitalization of $778 billion, as of June 4, 2018. Microsoft's ability to crush its competitors led to a two-year antitrust inquiry that sought to break up the corporation. Microsoft prevailed and continued to deepen its dominance in software development, Internet technology, cloud computing, mobile communications, and media with strategic mergers and acquisitions.

Its latest acquisition is open-source software development platform GitHub, which Microsoft purchased in a $7.5 billion all-stock deal. Here's a look a some of the company's most notable acquisitions.

LinkedIn

Founded in December 2002, LinkedIn is a social media website specializing in business relationships, finding job candidates, and networking. LinkedIn was the 28th most popular website on the internet, according to Amazon's website traffic ranked as of October last year. On June 13, 2016, Microsoft announced it would be buying LinkedIn for $26.2 billion, its largest acquisition yet. 

Since the deal went through, Microsoft has begun integrating the company into their ecosystem, combining LinkedIn data with Office 365. Microsoft's main hope is to use data from LinkedIn's over 500 million registered users to boost efficiency on many of their platforms. 

Skype Technologies S.A.R.L.

Entrepreneurs Janus Friis and Niklas Zennstrom founded Skype in 2003 with a team of software developers. Initially, the developers launched Skype as file-sharing software. Skype allows registered users to talk and video conference for free. It also gives users the option to purchase telephone numbers and by credit to call non-Skype landline and wireless telephones.

Microsoft is the third company to purchase Luxembourg-based Skype. eBay and the Canada Pension Plan Investment Board are previous owners. Microsoft acquired Skype in 2011 for $8.65 billion. Skype is now a wholly owned subsidiary of Microsoft.

Mojang

Created in 2009 by Markus "Notch" Persson, Mojang is a Swedish based video game studio known for creating and publishing one of the most popular video games of all time: Minecraft. With over 122 million sales as of February 2017, Minecraft has cemented itself as a cultural touchstone. The game has been ported onto game consoles, PCs, mobile, and smart TVs, and has remained popular with children for years. Microsoft bought Presson's ownership share of the company after he publicly stated in a tweet that he was tired of Minecraft and wanted to "move on with his life."

Microsoft spent $2.5 billion for the company and has since begun to turn the game into a transmedia property. With a movie in development, a cartoon series in the works, multiple VR and AR projects in development, Minecraft (and Mojang) has become one of the public mascots of Microsoft.

Yammer 

Founded in 2008 by Silicon Valley entrepreneur David O. Sacks, Yammer was designed as a social networking tool to be used for private communications in businesses. One of the main differentiators between Yammer and it's competition is that Yammer is a "freemium" program, meaning that while the program is free for all to download, companies must pay to access more advanced options. The company quickly took off, and Yammer now claims that 85% of Fortune 500 companies use their software. 

Microsoft announced in June 2012 that they would be buying Yammer for $1.2 billion. Eventually, Microsoft folded Yammer into their Office 365 team, where it has become a vital part of that program suite's ecosystem.

Hotmail

Originally founded in June 1996, Hotmail was one of the first free browser-based email services in the world, hitting one million subscribers in less than a year. In December of 1997, Hotmail was purchased by Microsoft for $400 million.

Microsoft had its fair share of trouble with Hotmail but it was eventually transformed into its current iteration: Outlook. Microsoft's email platform Outlook has hundreds of millions of users and controls 12% of the email market share, comparable only to Gmail and Yahoo.