How to decode tread patterns? I'm searching for new tires for my MTB, but I'm lost with the many options available, even within a single brand (like Maxxis). Under "Mountain" category alone, Maxxis lists 22 diferent tires, every one with many variants by size, compound and bead, while the only visible difference for me is the tread pattern. 

I understand that big knobs are better for mud, and small/none ones are better for hard surfaces, but how you translate the tread pattern (beside knob size) into handling characteristics? Can you look at a tread and says what it's good for? Is "climbs and brakes with authority thanks to the opposing parallelogram center tread design" (Maxxis Advantage) just marketing speak or it's for real?
Ask the guys you ride with and also complete strangers you meet on the trail, what they use and why. My guess is 9/10 times it was on the bike already, or it was on special. 

I have ridden for years, have a range of tires I have tried. Some I have liked better than others, mostly its a trade between speed, traction for braking and acceleration (not my strongest point anyway) and cornering. 

A tire is a compromise of the following 


weight
cost 
Straight line performance (one and/or both directions)
Cornering (Predictability and maximums)
Puncture resistance 


Add to this the types of terrain being ridden (the list gets bigger)


Rock 
Dirt 
Sand (soft)
Hard pack
Pavement


Then add 


Wet
Dry


If you are a casual weekend warrior like me, you got to the LBS, ask them for a tire for the trails you regularly ride (which they should know) and hope they gave you something half decent.