Peptide bond : In a polypeptide or a protein, amino acids are linked by a peptide bond which is formed when the carboxyl $(\mathrm{COOH})$ group of one amino acid reacts with the amino $\left(\mathrm{NH}_2\right)$ group of the next amino acid with the removal of water molecule.
Glycosidic bond : In a polysaccharide the individual monosaccharides are linked by glycosidic bond. This bond is also formed by dehydration. This bond is formed between two carbon atoms of two adjacent monosaccharides.
Phosphodiester bond : In a nucleic acid, a phosphate moiety links the 3'-carbon of one sugar of one nucleotide to the $5^{\prime}$ '-carbon of the sugar of the succeeding nucleotide. The bond between phosphate and hydroxyl group of sugar is an ester bond. As there is one such ester bond on either side, it is called phosphodiester bond.