.c;SPELL .TITLE;Spelling Checker .AP .HL1;Summary SPELL is a system of checking for spelling errors in text files on the RSX-11M operating system. The program SPELL does the checking and optionally may make changes, while DICTMK formats a file for SPELL to use. DCTNRY is a word looker upper that uses sends/receives with SPELL. They are written in FORTRAN-77 except for certain file access routines and alphabetic manipulation routines that are written in Macro. The program has been optimized as much as possible for speed. In non-interactive mode a file will be produced which contains all the words from the document that SPELL could not find in its dictionary. In interactive mode words can be replaced, added to the dictionary (DICTMK will need to be run again), or simply ignored. For an in-depth analysis of the operation of both programs, see the source code as it contains much comments. Automated extractions of comments (C+/C-) will tell the workings of all the routines. .hl1;Background The programs were written in FORTRAN-77 and were developed on a PDP-11/t55 with 6-RK05, running RSX-11M V3.2. Development has continued with our addition of 4 RL02 and upgrade to RSX-11M V4.1. The programs came from a desire on my part to have a system that could be used to check my submissions for