Joseph Gray, 28, a radiation therapist at Memorial Hospital of Carbondale who lives in Murphysboro, is pretty new to geocaching and says he just "stumbled" upon the sport.

"I was researching GPS units online and kept coming across the word 'geocaching.' Curious as to what it meant, I Googled it and ended up reading all about the sport," Joseph says. "And I was hooked after that."

Mostly, he goes out alone looking for caches. On some days, he takes his 3-year-old daughter with him and tells her they are going treasure hunting.

"It gives your kid orienteering and map-reading skills," Joseph says. "And hey, I'm going to use it if it will help get my kid outdoors and off the couch."

Here are some "rules" Joseph says you need to follow:

Always honor all law enforcement rules and regulations regarding geocaching. For example: State parks have rules and regulations regarding hiding a geocache. Make sure to get permission from the site superintendent before hiding a cache.

Always replace found caches as well as they were hidden.

Always leave something better than what you took from the cache.

Always log your finds online as a courtesy to the hider.

Cache in, trash out as you go geocaching. This essentially means you should take a bag with you while out geocaching, so that you can pick up trash along the way to help preserve the natural beauty of outdoor resources.

- Poornima Jayaraman