Esterification is opposite of saponification. In esterification :
$\mathrm{RCOOH}+{\mathrm{R}}^{\prime }\mathrm{OH}\stackrel{\mathit{\varnothing }}{\to }{\mathrm{RCOOR}}^{\prime }+{\mathrm{H}}_2\mathrm{O}$
Whereas in saponification :
${\mathrm{RCOOR}}^{\prime }+\mathrm{NaOH}\to \mathrm{RCOONa}+{\mathrm{R}}^{\prime }\mathrm{OH}$
(i) Uses of Esters : Esters are used in making perfumes.
(ii) Uses of saponification reaction : Used in making soaps and soap products on a large scale.