Four types of macromolecules are:
1) Nucleic Acids
Nucleic acids are comprised of the nitrogenous base (A, T, C, G), sugar and a phosphate group.
The bases are complementary to one another (A - T, C - G), and can create hydrogen bonds between one another. Complementarity is important for copying the information from one nucleic acid strand to another (useful for passing the genetic information across the generations, or for translating the information into proteins). Hydrogen bonding between bases is used for stability of the double stranded complex (DNA or RNA), which prevents easy degradation. Phosphate groups are important for linking individual nucleic acids to one another.
Lipids typically have hydrophobic and hydrophilic components (fatty acid tails and hydrophilic head groups), which allows them to create bilayers that can separate the environments from one another. This is important for creating boundaries within cells, embedding proteins that have hydrophobic parts, and allows for specialized permeation of molecules across those membranes.
Carbohydrates are molecules that can interlink with each other via covalent bonds, and breaking them up allows to release the stored energy. In addition, depending on the type of linkage, the resulting polymers can vary in strength, branch structure, which has a direct impact on where this polymer is found in nature and how easily it can be processed to release the energy.
Proteins are comprised of 20 chemically different amino acid types, which allows them to assume an infinite amount of 3d shapes and sizes, with vastly different physical, chemical and biological properties. The resulting diversity is crucial and supports variety of physiological functions (transport, enzymatic, structural etc.).