In 2000 Callaway sold the ERC II, a $625 driver over the USGA's 0.830 COR limit, with Arnold Palmer's backing. How the fight ended and what it changed.

In 1989 Ping sued the USGA and the PGA Tour for $100 million over the grooves on its Eye2 irons. Here's what happened, why old Eye2 wedges showed up on tour in 2010, and what it means for your clubs.

In best ball, everyone plays their own ball and the team takes the lowest score on each hole. Here's how it works, the Rule 23 details and how to play it smart.

A provisional ball is a backup ball you hit when your first shot might be lost or out of bounds. Here's when it's allowed, what you must say, and how to count strokes.