What does the notation $h \ll 1$ mean? The following screenshot is taken from some lecture notes on actuarial mathematics:



As you can see, the notation $h \ll 1$ is used here (in the first line of the proof).
Does anyone know what this is supposed to denote? I first suspected that it was a typo and was instead supposed to be $h < 1$ or $h \leq 1$, but the same notation is used on several occasions (leading me to believe that its use must be intentional).

It means “sufficiently smaller than”. So, $h\ll1$ means that $h$ is sufficiently smaller than $1$ (but still greater than $0$).
