How They Work
The name says it all. Inkjet printers use printheads, which contain a series of nozzles, to spray microscopic jets of ink onto paper to create an image. The more dots they put on the page, the higher the resolution and the sharper the image (to a point; there's more to learn about printer resolution specs).
Ink Tanks
Inkjets use ink tanks or cartridges. There can be multiple ink tanks in an inkjet printer (my Pixma has five), or there can be a single tank that holds both color and black inks. When multiple tanks are used, typically there is one black tank just for text, and another black tank for printing photos. The more tanks there are, the greater the subtleties in the colors of prints (high-end inkjets can have even more than five tanks).
Inside the printer, a small motor pushes the printheads across the page while the paper is fed through the machine. For draft images, this process happens quite quickly, while if you set your printer to print in its Best mode, the printheads will make multiple passes across the page.
PPM
Printer speed is typically measured in pages per minute (PPM), but you can see how this might be misleading sometimes; the number of pages that come out in one minute can be a lot or a few depending on how sharp you want the result to be. It also depends on whether you’re printing monochrome or color images, as well as the size of the image being printed. So take manufacturer claims of PPM with a grain of salt.
Consumables
Good-quality inkjet printers are available for under $100, so they seem like natural choices—cheap and high quality. But you also need to consider the consumables, such as the cost of ink tanks as well as any specialized paper needed.
The five tanks on the Pixma need to be replaced (after regular, daily use) about once every two months or so. It typically costs more than $50 to replace all five—that’s nearly a third of the price of the printer itself.
I don’t print many photographs or need high-quality paper, so my paper costs are fairly low. But if you are printing documents for work, you need to use paper made for inkjet printers. Why? Because inks are water based, and no matter how small the printhead nozzles, the ink will bleed into the paper and sharpness will be lost. Buying 200 sheets of inkjet paper can set you back another $30 or so.
Bottom line: If you intend to print a lot, check the prices of the consumables before you buy a printer. If you’re only going to be printing documents and need them to look their absolute best, consider a laser printer instead. But if you’re after a versatile machine (printer, scanner, and fax) and don’t need to print often, an inkjet is a great value.
