The visual mode "vi" editor is a successor to "ex" and "ed" which were and are suited to stream mode editing.   See "man ex", "man ed", etc at the UnixPrompt% ..

Other relatives include sed, the true stream editor. When you get in tight with sed you may well be ready for perl an advanced command (not compiled) text manipulation language which is usually an addon to higher priced operating systems (vendors don't want to support exotic tools without more money).

Emacs is the FIRST choice of long haired Unix editor users.  This page edited with GNU EMACS Version 19.34.1 on i386 (FreeBSD). Emacs is the most feature friendly editor for graphic environment to be found in Unix windows. Invoked "emacs filename" The <ESCAPE> key is the prefix "meta" key to many emacs commands. We Exit with save Ctrl_X..Ctrl_C..y (a triple succession of keys). Help comes from Ctrl_H ... and maybe followed with appropos to get us help on a particular item. Modern emacs is very graphic and even has SGML / HTML recognition modes, Ctrl_X..1 returns us from split screen to ONE screen, Ctrl_X..b lists the last current buffer so when you get lost in another buffer you can see the name to return to .. Invoking emacs with NO FILENAME, enters the turorial mode if it has been properly installed ("info").

One more useful to some tastes is the textedit command which is only native in a few Unix versions, Solaris and prehaps HP-UP, which will allow a true WYSIWYG editor environment but with precious few frills.