|Some cartridges are merely ink tanks, others have an integrated print head in the bottom of them. The ones that are ink tanks are for printers that have a multiple port print head built into the printer.|
Some cartridges have a chip, most if not all are in the ones that are ink tanks, that must be re-set when the cartridge is refilled. The chip has data entered on it as the cartridge is used, and if you don't re-set it, you'll have problems because of that, and in some cases eventually the printer will refuse to use the cartridge after enough time or number of uses has gone by. A local place that refills cartridges usually has a chip re-setter and they will re-set the chip as part of their service. If you refill the cartridges yourself, you'll need to buy a chip re-setter for your cartridge type(s).
If you live in a reasonably large place, there are local places, sometimes in the ailes of a mall, that will refill your cartridge for about half the price of a new one.
Look in your Yellow pages.
Or - if you search on the web, there are web sites where you can buy refilled, re-set if required, brand name, or new generic cartridges, for less money than having your cartridges refilled locally, and they also often have bulk ink kits and chip resetters if required if you want to refill the cartridges yourself, and most have instructions on their web site that tell you how to refill your particular cartridges..
(DO NOT buy ink kits that have "universal ink" - you will probably have problems if you do.)
It's very important to NOT allow ink to have a chance to dry out and clog in the print head or in the ink port . When a cartridge runs out of ink, if that's the only one you have, DO NOT remove it until you're ready to have it refilled or refill it yourself.
If you have more than one cartridge of the same type, install the other one that has ink, and refill the one that has run out of ink as soon as you can.
If you need to, place it in a plastic bag along with a wet tissue (don't let it touch the ink port or print head on the cartridge) , tie up or seal the bag, for a short time.
New cartridges often have a device that sealed the ink port or the print head that you removed before you installed the cartridge - if you still have that, if it can be installed on the used cartridge, install that (you may need to tape it in place) then you can store it before you refill it for a longer time. Or if it's an ink tank, you can use black electrical tape stretched tightly over the ink port (clean off any dried ink on it's edges before you do that).