The Free On-line Dictionary of Computing (30 December 2018):

Stanford Artificial Intelligence Language

    (SAIL) Dan Swinehart & Bob Sproull, Stanford AI
   Project, 1970.  A large ALGOL 60-like language for the DEC-10
   and DEC-20.  Its main feature is a symbolic data system based
   upon an associative store (originally called LEAP).  Items may
   be stored as unordered sets or as associations (triples).
   Processes, events and interrupts, contexts, backtracking and
   record garbage collection.  Block- structured macros.  "Recent
   Developments in SAIL - An ALGOL-based Language for Artificial
   Intelligence", J. Feldman et al, Proc FJCC 41(2), AFIPS (Fall
   1972).  (See MAINSAIL).

   The Stanford Artificial Intelligence Language used at SAIL
   (the place).  It was an ALGOL 60 derivative with a coroutining
   facility and some new data types intended for building search
   trees and association lists.

   A number of interesting software systems were coded in SAIL,
   including early versions of FTP and TeX and a document
   formatting system called PUB.

   In 1978, there were half a dozen different operating systems
   for the PDP-10: WAITS (Stanford), ITS (MIT), TOPS-10 (DEC),
   CMU TOPS-10 (CMU), TENEX (BBN), and TOPS-20 (DEC, after
   TENEX).

   SAIL was ported from WAITS to ITS so that MIT
   researchers could make use of software developed at Stanford
   University.  Every port usually required the rewriting of I/O
   code in each application.

   [Jargon File]

   (2001-06-22)