Can you use regular paper in a printer?

Mark Swarthout's answer is not completely accurate. The paper that a printer can use is defined by the type of printer and the standards as set by the manufacturer. For example, with the laser printers I have in the office, their manufacturer specifies that the paper must be between 19 and 24 pound stock for regular paper, 20 to 24 pound stock for envelopes, 24 to 28 pound stock for thick paper, etc. These are pretty standard paper requirements for most printers. If the paper you intend to use is outside of these standards (such as vellum paper), then chances are that they will not work and could actually damage your printer. For example, in the case of vellum paper, an inkjet's ink could cause the material to fall apart and cause jams inside the printer while inside a laser printer, it may not feed correctly through the various rollers, accept the static charge of the charging roller/corona wire, or the properly absorb the heat of the fusing assembly, thus leading to paper jams, incomplete print images, or possibly scorching of the paper.

Another thing about which to be wary in the case of laser printers is that the paper's brightness is not too high. The brightness determines how "white" the paper is or, more specifically, how much light it reflects back. The improper level of brightness can lead to poor print images. Most printers are designed for a brightness range of about 88 to 102.

All these specifications are given with each ream/box/case of paper and what the printer can accept are listed in the specifications section of your owner's manual.

If you have any trouble determining what your printer can use or have other questions, feel free to drop me a line and I will be glad to help you.