Microprinting is one of many anti-counterfeit

Counterfeit

To counterfeit means to illegally imitate something. Counterfeit products are often produced with the intent to take advantage of the superior value of the imitated product...

ing techniques used most often on currency

Currency

In economics, currency refers to a generally accepted medium of exchange. These are usually the coins and banknotes of a particular government, which comprise the physical aspects of a nation's money supply...

 and bank

Bank

A bank is a financial institution that serves as a financial intermediary. The term "bank" may refer to one of several related types of entities:...

 checks, as well as various other items of value. Microprinting involves printing very small text, usually too small to read with the naked eye

Human eye

The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...

, onto the note or item. Microprint is frequently hidden in an inconspicuous, unnoticeable area on the note or item. For example, on the series 2004 United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 $20 bill, microprint is hidden within the border in the lower left corner of the obverse (front) side as well as the Twenty USA background. However, microprint is sometimes placed in a prominent location on the item, and may even be labeled with an MP symbol as a warning that the note or item contains microprinting. On most bank checks in the United States, the line on which the account holder signs his or her name is microprint text, and the microprint line usually includes the MP symbol next to it. An additional safety feature often used is an easily overlooked spelling error inserted somewhere in the microprinted text. For instance in old Finnish passports, there was a microprinted repeated text "Suomi Finland" which in one and only one instance was misspelled as "Soumi Finland".

Microprinting works as an anti-counterfeiting feature through the fact that text of such small size is very difficult to reproduce accurately during attempts to counterfeit the note or item on which it is printed. When the note or item is placed in a photocopier

Photocopier

A photocopier is a machine that makes paper copies of documents and other visual images quickly and cheaply. Most current photocopiers use a technology called xerography, a dry process using heat...

 or computer

Computer

A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...

 scanner

Image scanner

In computing, an image scanner—often abbreviated to just scanner—is a device that optically scans images, printed text, handwriting, or an object, and converts it to a digital image. Common examples found in offices are variations of the desktop scanner where the document is placed on a glass...

, a line of microprint text will appear to the copier or scanner as a dotted or solid line, which will then appear in the same manner on the counterfeit note or item when it is printed. Likewise, attempts to counterfeit using a printing press

Printing press

A printing press is a device for applying pressure to an inked surface resting upon a print medium , thereby transferring the ink...

 do not accurately reproduce the microprint, because the text is too small to engrave

Engraving

Engraving is the practice of incising a design on to a hard, usually flat surface, by cutting grooves into it. The result may be a decorated object in itself, as when silver, gold, steel, or glass are engraved, or may provide an intaglio printing plate, of copper or another metal, for printing...

into the printing plates using methods available to the general public and to counterfeiters. Thus, microprinting, along with other anti-counterfeiting methods used on the note or item, ultimately serves to confirm the fact that the note or item on which it is printed is genuine.