Cash in itself has no real value; it’s what the money represents that gives it value. With money, we purchase things we need in order to live.

But when someone fools the system by printing and spending fake or counterfeit money, innocent people become victims. Small businesses that do not spot the bogus bill until it’s too late end up losing money. Likewise, citizens are both victimized and embarrassed when they inadvertently try to exchange a counterfeit bill for goods or services.

Local law enforcement agencies want to warn merchants and citizens to be on the lookout for fake money. One of the best lines of defense is to be familiar with what real money is supposed to look like.

Newer bills contain watermarks, which are transparent replicas of the presidential portrait located in the blank space to the right of the portrait. These are embedded in the paper and are visible by holding the bill up to a light.

Also note the security thread, an invisible line indicating the bill’s denomination, which usually alternates with the letters “USA.” The thread is in a different location for each denomination and also becomes visible in front of a light.

Real money also contains other features that are hard to duplicate, such as color changing ink and small blue and red fibers.

Here are a few tips for merchants who encounter someone trying to pass a counterfeit bill:

Don’t put yourself in danger

Don’t return the counterfeit money to the passer

Observe the description of the suspect, the description of any accomplices and the tag number of the vehicle

Delay the person with an excuse for as long as possible

Contact law enforcement

Write your initials and the date in the border of the suspect note

Do not handle the note; instead, place it in a clear plastic bag or protective cover

Surrender the counterfeit money only to law enforcement or mail it to the nearest U.S. Secret Service field office.