A vi editor quick-start tutorial

This is a quick-start tutorial for the vi text editor which is available on most Unix or Unix-like systems, including Linux, macOS, Solaris, HP-UX, AIX, FreeBSD/OpenBSD/NetBSD, and Windows, and on some niche OSes too. vi,  or a variant of it (e.g. vim/elvis/nvi, etc.) is one of the few text editors which is almost guaranteed to be present (or can be installed) on all of these systems.

See: https://en.wikipedia.org/wiki/Vi#Impact

So it's useful to have basic knowledge of its use, since it is widely applicable.

Although the vi variants have somewhat different command sets, they all share a common subset (consisting of the most commonly used operations), and a common editing model. This tutorial covers some of that subset, enough for a beginner to get started using vi to perform day-to-day text editing tasks, without getting lost in arcane command syntax.