The quality of the prints depends on the quality of the toner, as the toner is actually the ink for laser printers.

The toner is an extremely fine synthetic powder packed into a cartridge. This cartridge is then inserted into your laser printer according to the manufacturer's instructions. And this is where the role of such toner comes into picture.

Let us understand in short the role of these toners as soon as a page is inserted in the printer. There are a few steps in printing a page with the help of a laser toner:

In the first step, printer receives an image to be printed from your computer.

The lasers project the image onto an electromagnetic drum inside the printer.

According to the image, the drum is charged positively and negatively, and at varying levels of charge.

The drum in turn attracts ink from the toner in the cartridge according to the charges the colors are attracted to.

The drum rolls the image onto a page of paper, the page goes through a heating device to melt or burn the color onto the page, and the page is ejected.

This is when the toner is used in the printer. Most of the toners are designed to print a few thousand pages before needing to be replaced. Similarly, the drum also wears out from all the positive and negative charges it gives off, and needs to be replaced every 10,000 to 30,000 pages.

Some printers are made with cartridge-and-drum replacement units in mind, while other printers are designed to separate the cartridge and drum. This way, when the cartridge runs out of toner, you don't have to replace the longer lasting drum with it. This saves you money.

There is a huge ongoing debate on the use of compatible toners. They are widely used besides the printer companies regular warnings on the illegal aspects and the harms they can cause to the printer.

However, besides such warnings, the compatible toners are now a days common forcing the companies to change their stance and to launch economically priced toners.

Most manufacturers, and some third-party distributors, will give you money or discounts in exchange for your old toner cartridges. They in turn replace the guts of the cartridge, refill it with toner, and resell it at a big discount.