The cytoplasm is located within a cell's membrane, but not inside a cell's nucleus. The cytoplasm is an important part of the cell, because it houses many of the organelles and nutrients that keep a cell functioning.
Apart from the nucleus, all of the cell's organelles are in the cytoplasm. Along with the protein filaments of the cytoskeleton, the cytoplasm also provides structural support to the cell. Additionally, it contains soluble proteins as well as packets of insoluble materials, including energy-storing substances like starch and glycogen. The cytoplasm also stores cellular waste until the blood takes it away. Many of the cell's most important functions, such as glycolysis and cell division, take place in the cytoplasm.