Help with Madden Glitches!

What are Madden glitches?  I have never experienced problems while playing my game but I have read many forums where people experience glitches.  Can someone please explain to me what this means? Is this what happens when something doesn’t work properly in the game?  I have tried to look it up online but in order to get any help they always ask you to pay money to get some kind of glitch guide.  I don’t want to have to pay any money to figure out how to fix a game when it should be working properly in the first place.  If someone could please explain to me what the glitches are and how I can find out how to fix them (without paying money) that would be great.  Please post your comments and suggestions below!