油印是在计算机打印未流行前的一种用蜡纸印刷的方法。由于所需的工具和材料简单，曾十分流行于学校和企业。主要工具是誊写钢版，誊写笔，蜡纸，油墨，白纸。

最简便的蜡纸印刷方法，是将已经刻写完毕的蜡纸用夹子固定上头，一手执蜡纸另下头，将一张白纸放在蜡纸下，另一手拿一把平头毛刷，沾一些油墨，在蜡纸上，由上至下，由左至右，均匀地刷一遍，一张油印品告成。如此可重复多次，引出多张油印品。讲究一些的可用滚筒油印机，将油墨均匀涂刷在油印机滚筒上，然后卷上刻写过的蜡纸，在滚筒下安放一叠纸张，手摇滚筒印刷机的摇把，每转一圈，可印出一张油印页。

The stencil duplicator or mimeograph machine (often abbreviated to mimeo) is a low-cost duplicating machine that works by forcing ink through a stencil onto paper. The mimeograph process should not be confused with the spirit duplicator process.

Mimeographs, along with spirit duplicators and hectographs, were a common technology in printing small quantities, as in office work, classroom materials, and church bulletins. Early fanzines were printed with this technology, because it was widespread and cheap. In the late 1960s, mimeographs, spirit duplicators, and hectographs began to be gradually displaced by photocopying.