They're also the new language of choice for online predators.

As many primary and secondary school students receive their own devices for use in the classroom, they may also receive something much more sinister, police warn.

Online predators are targeting children through unsolicited texts and emails, using encoded messages designed to fly under the radar of parents.

The AFP have revealed a glossary of acronyms and emojis that should raise alarm bells for parents.

"Some terms, slang or emojis may seem to be innocent symbols, however, they may signal a highly-sexualised conversation," Australian Federal Police Commander Hilda Sirec said.

They include the 'bowl of noodles' emoji, (shortened to 'noodes') which is code for nude photographs. Likewise, the 'husk of corn' emoji translates to online porn.

Some predators are contacting children through school email addresses, which they can find using a simple back-to-school post from mum and dad, a University of Wollongong academic has warned.

"When people actually post on social media, and especially when they show for example, uniform, it actually identifies the children's school," Professor Willy Susilo, Director of the Institute of Cybersecurity and Cryptology, said.

"And the most dangerous thing is, some of the predators will then be able to contact these children directly.

"If we know the name of this kid, because usually the parents post the name, then they can use the standard domain for New South Wales Education."

While many parents want to celebrate and share what their children are doing, it's important to control who sees it, and make sure your friends and family are on the same page, Professor Susilo said.

"I've seen a case when actually, the parents had done the right thing," he said.

"They shared with just close family. But one of the close family members actually posted [the photos] elsewhere."

As many children attended school virtually last year, leading a life completely "offline" seems impossible. The way forward isn't to log off completely, Professor Susilo said.

Restricting kids' access to Facebook Messenger, turning on parental controls and monitoring their time online are all ways to keep kids safe in the cyberspace, he said.