Today we suppose that of all the options you chose to buy original cartridges. They are said to be most reliable and provide high quality of printing with every printed page. Another well-know fact is that original cartridges are more expensive compared to other alternatives. When you give away you own money for a brand cartridge, I bet you have to be sure it's not a fake.
From two articles on TCD blog you will know how to identify original ink cartridges and toner cartridges (HP cartridges case study)