In Japanese manufacturing and DIY, you’ll often hear the words neji (screw/threaded fastener), bolt, and bisu (Machine Screws). They’re used interchangeably in daily conversation, but in practice there are clear differences in how each term is typically used.
This page explains the fundamentals: what “threads” really mean, how bolts differ from smaller screws, and what people usually mean by “bisu.” We’ll also cover representative types, their typical applications, and how their shapes affect installation and performance—useful for maintenance technicians, designers/engineers, and DIY users choosing the right fastener.
