What is the function of the Golgi apparatus?

The Golgi apparatus is one of the most significant organelles present in most of the eukaryotic cells. It is a membrane-bound sac and is also known as Golgi body, Golgi complex, etc. The key functions of this organelle are as follows:
It carries out the processing of the proteins generated in the endoplasmic reticulum.
It transports proteins to different parts of the cell.
It involves the modification of cargo proteins by Golgi enzymes.
It imports nucleotide sugars from the cytosol in order to carry out the processes of glycosylation and phosphorylation.
It breaks down proteins and forms small, active fragments.
The addition of sulfate groups to the proteins takes place in the Golgi apparatus.
Phosphate molecules are also incorporated into the proteins in the Golgi apparatus.
It transports the lipids around the cell.
It is important in the creation of lysosomes.
It involves the processing and packaging of the macromolecules (for example, proteins and lipids).
It involves the synthesis of proteoglycans.
The Golgi apparatus can also be thought of as the "post office" of a eukaryotic cell.