Currently Being ModeratedJan 8, 2013 3:32 PM (in response to Therese2018)
There is no data loss, when doing a reset, think of it as rebooting your computer.
Hold down the home/power button together until you see the apple logo and then release, then wait for the phone to boot back up.
Also you should be syncing and backing up your phone on a regular basis. http://support.apple.com/kb/HT1766