Baryonic matter is ordinary matter composed of protons and neutrons.
Our bodies are made of protons, neutrons, and electrons. Virtually all of our mass comes from the protons and neutrons in the atoms we are made of, so we are therefore made of baryonic matter. On the largest scales, redshift surveys of large numbers of galaxies reveal that clusters and superclusters are arranged in patterns of sheets that surround voids, within which few galaxies can be found. In general it has been found that the largest void seen is limited only by the size of the volume sampled by the redshift survey. The Great Wall is an immense sheet-like structure of galaxies measuring Mpc in size.