At what point in time did 1 GB become 1000 MB?

Question

Informatics

I remember sitting on a class, the teacher was talking about the size of the data, that 1 GB = 1024 MB, was it in another universe? Computer science books say 1 GB = 1024 MB.

Answer 1

https://ru.wikipedia.org/wiki/Byte#Derived_units

Answer 2

Since 1999, officially the kilo/mega/giga values ​​are a derivative of ten, in order to comply with C standards (not a programming language, international system of units ).
And with the suffix bit - the derivative of two.
1000 - kilobyte
1024 - kibibyte
In everyday life, many are still not aware, but in fact it has a noticeable value only in certain circles.