IT Services Circle

Sep 19, 2026 · Fundamentals

Why Linux Has /bin and /usr/bin: A 1971 1.5MB Disk Crisis

The split between /bin and /usr/bin originated in 1971 when Ken Thompson and Dennis Ritchie ran out of space on a 1.5MB PDP-11 disk, prompting them to spill overflow commands onto a second disk mounted at /usr—a pragmatic hack later mythologized as intentional design, causing decades of confusion until modern distributions merged them via usrmerge.