IF YOU’VE taken a golf lesson and promptly forgotten everything you were taught -- or never managed to absorb any of it to begin with -- raise your hand.

If your arm’s up, you may want to try a company called GolfTEC, which is known for its high-tech approach to golf instruction but comes with another huge plus: Every lesson and the accompanying pictures, with the instructor’s audio, notes and suggested video drills, are available any time on the Internet.

You can work on your swing at home, maybe even in the office or in a hotel room, anywhere you have access to the web . . . and a high enough ceiling. Before you go to the driving range, you can review a lesson and the areas you want to work on from a lesson you took a month ago or, for that matter, a year ago. (The cost? $165 for a one-hour swing evaluation and lesson; packages run from $395 to $2,695.)

Established in 1995, GolfTEC claims to have provided 10% of the golf instruction in the country last year. Most of it takes place indoors, in practice bays with sensors connected to the student’s shoulders and hips and two video cameras providing front (to detect lateral movement such as swaying) and down-the-line angles (to show swing path).

The instructor puts your swing video on a laptop located next to the tee, side by side with a PGA Tour pro for comparisons of body position during the swing. The sensors show the amount of bend and turn in the hips and shoulders, and an audio signal can be activated so that it beeps when the student’s posture is incorrect during the swing, biofeedback that enhances muscle memory.

The fact that you’re inside, smacking a ball into a net a few feet away, is actually a good thing, according to Frank Liu, an instructor at GolfTEC in Huntington Beach.

“If you’re going to make a swing change, make the swing change,” Liu said. “You shouldn’t be worrying about ball flight. If you make the correct changes, the ball will go where you want it to.

“We offer instruction outside, even on-course instruction, but we want to build the foundation of a good swing first.”