sir/madam please explain to me in detail the saponification reaction by taking general examples instead of standard ones like sodium stearate

to help u send the explanation i require i am writing the doubts that i have regarding saponification reaction

1.are oils esters?

2.in saponification reaction a salt of sodium and glycerol r formed so..how is it a reverse of esterification reaction?

with the explanation also give me a general equation for saponification reaction