Naturally occurring amino acids have 3 simple components; Amino group, tetrahedral carbon (alpha carbon), and a carboxylic carbon. The thing that makes them different is the group attached to the tetrahedral carbon.
Each amino acid is different due to the group attached to the alpha carbon. In general, there are 3 types of groups attached to the alpha carbon (R-groups): Hydrophobic, Polar (non Ionic), and Ionic. Hydrophobic R groups include things like Valine, Isoleucine, Phenylalanie. Polar R groups include things like Asparigine, Serine, Tyrosine. Ionic groups include things like Aspartic Acid, Lysine, and Argenine.