Back in 1994 — yes, almost 30 years ago! The Beowulf cluster could be used for parallel computations in which many calculations or processes are carried out simultaneously between many computers and coordinated with message-passing software.
For the next 10ish years, more and more people followed the Beowulf model.
Over time, these systems have become more complicated with multiple tiers of storage and groups of compute resources, but the basic Beowulf framework has remained the same for thirty years.
Generally, every HPC user has to follow the same general steps for all HPC systems: SSH into interactive node(s).