Windows

Microsoft Windows is a family of operating systems developed by Microsoft since 1983. It currently uses the Windows Explorer shell. The latest release is Windows 11.

The hype of 1983
In the early 80s, Microsoft gained popularity for its applications like Word for DOS. But Microsoft was working in something to compete against the Macintosh's friendly user interface. At COMDEX 1983 in November, Microsoft demonstrated a new upcoming product, "Microsoft Windows", running on a personal computer with monochrome graphics, and with various applications running alongside each other in "windows". They really hyped people about it, promising it as the software of the future that will be installed on every PC.

A hard market
After the hype of 1983, they released their product under the name of Windows. Unfortunately it didn't get the success they expected, mostly because it wasn't exactly what was promised to the people. But despite this, Windows found its niche place in the market alongside other shell programs.

Getting shaped
After the excessive hype and a regular market success, Microsoft launched Windows 2.0 in 1987. This version got significant improvements over its predecessor. Examples of this are overlapping windows and Expanded Memory Support (EMS).

Popularity increases
After Windows 2.x, Microsoft decided to release a new version of Windows, Windows 3.0. This version was finally getting a significant user market, making Microsoft a serious player in the software industry.

Windows NT
After Microsoft broke its partnership with IBM, they began development of their new own OS. They initially called it NT OS/2, NT standing for New Technologies, while they kept OS/2 in the name due to being based on OS/2. Later, to avoid any copyright issues, they simply called it NT. Some of the goals of this OS were stability, security and portability, last one is a reason why it was heavy compared to their already existing Windows OS (It was programmed in C instead of assembly, thus making it portable yet heavier).

Windows 9x
These were the consumer versions of Windows released in the 90's. These were known for still being based on DOS. The first was Windows 95, which gave its massive success to Microsoft. This release gained popularity and it was becoming a defacto standard on many PCs. Here's where Windows started to really grow, practically monopolizing the market. This lead to a lawsuit in the late 90s/early 2000.