Insects are an incredibly diverse class of largely terrestrial arthropods, with a million named species and many more to be discovered. Trillions of individuals are farmed for food and feed each year, with trillions (maybe quadrillions) more impacted by other kinds of human use and management. The question of insect pain is an open one, without broad scientific or philosophical consensus. Here, I present the history of the science on insect pain and the main neurobiological and behavioral evidence used to support and reject the idea of insect pain. The pain and suffering experienced by farmed insects during rearing, transport, and slaughter is reviewed, albeit from a somewhat speculative lens (given the uncertainty of insect pain at all, and the lack of validated tools for assessing pain in any insects). Analgesics and anesthetics that may work for insects are reviewed, as well as attitudes on insect pain from consumer, producer, academic, and other perspectives. Other arthropods - besides insects and crustaceans - are briefly reviewed, before concluding with the complexity of moral caution in the insect case.