OK. On datasheet of transistor 2N4401 there are many DC current gains (hFE). Which one is useful. I want to use it over 5V and 60mA.
Yes - agreed. Here in germany, we do not discriminate between hFE and hfe.This sheet has two different gain specifications
hFE (DC current gain) which is beta and has many specified conditions.
hfe (Small-Signal Current gain) at one specified condition, which the the small signal gain.