"Strobists" are the followers of teachings of David Hobby published in his blog, "The Strobist". Strobism is usually characterized by using small flashes (designed for on-camera use) in manual mode off camera to achieve better lighting than available from ambient lighting. The flashes are often accompanied by portable and/or DIY light modifiers and set-up gear.

In recent years, studio strobes (still in manual mode) have also been discussed in Strobist articles. The earlier articles (in "Lighting 101" and "Lighting 102" series) are still relevant and give a sound base for anyone wanting to get in command over their lighting, even if manual mode is not the ultimate goal.

You might run into the term in macro photography because more light is often welcome for macro, so cheap and flexible ways of creating and controlling it are nice to know. Originally strobism, however, is mostly concentrated on on-site (off-studio) portraiture. The techniques require some time to set up and adjust equipment with a specific outcome in mind, so they are more suitable for arranged shots than live event coverage.