Why are Windows semiannual updates named H1 and H2?

Windows issues monthly updates, but the bigger updates happen twice a year. The one that happens in the first half of the year is called the H1 release, and the one in the second half is the H2 release. The letter H refers to “half”, which is the same pattern used by finance people to refer to the first and second halves of fiscal years. (Quarters are abbreviated Q, so Q2 means “second quarter”, for example.)

You may remember that the semiannual updates used to be called the Spring and Fall releases. For example, we had the 2017 Fall Creators Update and the 2018 Spring Update. Why the name change?

It was during an all-hands meeting that a senior executive asked if the organization had any unconscious biases. One of my colleagues raised his hand. He grew up in the Southern Hemisphere, where the seasons are opposite from those in the Northern Hemisphere. He pointed out that naming the updates Spring and Fall shows a Northern Hemisphere bias and is not inclusive of our customers in the Southern Hemisphere.

The names of the semiannual releases were changed the next day to be hemisphere-neutral.