If you saw 53X on your kid's phone, would you know what it meant?
"They're numbers and letters but I have no idea what they mean," says one parent.
The number five, the number three and the letter six stands for sex and it's one of many new codes teens are using to hide their sexting according to police in Europe.
"They're always changing. They're trying to be sneaky, hide things be faster than their parents for sure."
Some of the other new codes are c-u-4-6, which means see you for sex.
g-y-p-o, code for get your pants off, and i-w-s-n which means I want sex now. These new codes have parents worried.
"I am concerned.... if they had a code. i probably wouldn't be able to figure it out," one parent in Rehoboth said.
If you talk to the teens themselves it's easy to see why they go through all of the trouble of hiding their racy texts.
"Some people have overprotective parents. They think their parents won't decipher the teen code," an 18 year old from Laurel said.
Sexting is illegal in the state of Delaware, and mental health counselor Cleveland Ray says social media is partly to blame for the behavior.
"It's indicative of toady's lack of social skills and ways to socialize that are appropriate," Ray said.
Of course there are many teens who are not a fan of sexting.
One teen from New Castle said "I think it's inappropriate. It goes against your parents and yourself."
One of the most important things parents can do is keep communication with their kids about their phone usage.
"I think it's very important to regularly check your kid's phone and to look through apps to see what they are doing behind the scenes."