Good technical explainer on fiber optic cable installation. It goes into the "why" behind Single-Mode (laser, 9-micron core) vs. Multimode (LED, 50/62.5-micron core). It clearly explains why distance and bandwidth needs dictate the choice. This is a perfect link for any DFW tech's reference library or for training new installers. https://www.cablingindfw.com/fiber-optic-cable-installation-single-mode-vs-multimode/