Analine is an aromatic amine and it has a benzene ring which is electron withdrawing in nature. Because of this, the lone pair of electrons on nitrogen is not readily available for donation, as it is involved in the resonance. whereas methylamine is an aliphatic amine and the methyl group is electron donating in nature so the lone pair of nitrogen in methylamine is easily available for donaton because there is no resonance in methyl amine. Thus methyl amine is more basic than aniline.
