OK, it doesn’t really stand for panic, but it can be thought of that way. The P mode on your camera sets everything in fully automatic, so all you have to think about is composing the shot and pressing the shutter release button. So if you have been playing around with camera settings and that shot of a lifetime comes along and you don’t want to mess it up, you can set your camera to P to get the shot.
This means the camera will select an ISO setting, Shutter Speed and Aperture for what it thinks is the best exposure for the conditions it can detect. Most cameras will allow you to override certain settings in P mode if you think it’s needed.
The P mode can be useful for people who are new to photography and don’t want to use any of the manual settings, and it can be good for getting that spur of the moment shot so you don’t have to worry about any camera settings and you just want to record the moment.
Using the P mode is fine, but exploring the other modes, giving you more control over the image, will help you produce better quality work and understand photography a lot more.