Yes AC/DC is one of the greatest rock bands to ever play but it also stands for alternating current and direct current. Alternating current changes direction periodically while direct current moves in a straight line. Most electronics use direct current. AC delivers power to houses and office buildings because it travels over distances better.
NPT or National Pipe Thread, is a U.S. standard for tapered threads on threaded pipes and fittings. NPT goes back to 1864 when William Sellers created a standard for nuts, bolts and screws.
TPI stands for teeth per inch and no, that’s not how they measure a shark’s danger level. Teeth per inch indicate types of saw blades. Higher TPI blades leave a smoother surface but cut slower than lower TPI blades. Check out some essential bandsaw tips for your next project.