Are lighting tracks universal?

Will light fixtures from one manufacturer fit into the track of anothers? All of the track I’ve worked with uses the same layout, ie, one conductor on one side, two on the other, but I’ve never checked to see if all of the dimensions are the same. Is there any interoperability between different brands?

Not that I’ve seen. Halo, Juno, and Lightolier all use proprietary track sections, fittings, and heads.