Hey all. I’ve been thinking of creating a website related to street lighting, similar to StreetLightOnline and LeoLamppost’s. What should I use to create mine’s?

Break a leg, good luck

If you're talking about the forum and gallery software, L-G went with Coppermine Photo Gallery and Simplemachines Forum. But Simplemachines is old and not very elegant, so you might want to use Discourse instead. Discourse is elegant and full-featured. See how it looks-on the Straight Dope Message boards. You might have to create your own login/signup window that logs you into/signs you up for the forum and gallery at the same time. All three of these software solutions are open-source. I do not recommend closed-source for a forum software or most web stuff for repairability reasons.Have fun making the site!