What does the "SUDS"mean on my washing machine display?

It means you are using detergent improperly.
 
If your washing machine has the word "SUDS" on the display, it has detected an over-sudsing condition, and will stop for a short period to allow the suds to dissipate. This error code is usually caused by too much detergent, or the wrong type of detergent.

Samsung recommends using "HE" (High Efficiency) detergent, which is designed specifically for high efficiency front loader washing machines. "HE" detergent has high efficiency cleaning capabilities with low sudsing properties. Non "HE" detergent normally has high sudsing properties, and will cause excessive amounts of suds in your machine.

If you are already using "HE" detergent and your washing machine is displaying the "SUDS" error code, you may be using too much detergent. Please follow the detergent manufacturer's suggested amount of detergent. There are many different concentrations of laundry detergent. For example: 1x, 2x and 3x. Be sure to reduce the amount of laundry detergent accordingly.