deriv LSK ETT STT aSTA ALPH OLDHOMEPAGE NEWHOMEPAGE

/al / अल्

The word /al means "all letters". TBP, it means all the letters that appear in the /zivasUtra, from the a अ A आ at the very start to the h ह् at the very end.

/H and /M are not "/al" letters, because they do not appear in that list.

But there is no A आ in that list, there is only a अ i इ u उ. Is A आ not an /al letter?

It is. The a अ in the /zivasUtra means "a अ and A आ". See aNuditsav....