Focal is an interpreted language like basic designed for quickly and easily writing program. It dates from the late 1960's. A description of Focal and tutorial on using it: Introduction to Focal 1969 promotional handout (Douglas W. Jones).

The following is the online help that came with the OMSI Focal 71

WHILE WRITING A PROGRAM, YOU MAY ASK 'HELP' TO REVIEW SECTIONS,
PHRASES, WORDS OR SYMBOLS LISTED BELOW BY GIVING THE DIRECT COMMAND ---
'L G HELP'.  SHOULD YOU WISH TO RETURN TO YOUR PROGRAM BEFORE HELP'S
RESPONSE IS DONE, HOLD DOWN THE 'CTRL' KEY WHILE STRIKING THE
'P' --- THEN TYPE 'G' AND HIT 'RETURN'.




               INDEX FOR 'HELP' --- PS/8 FOCAL, 1971



      COMMANDS               SYMBOLS          FUNCTIONS
--------------------   --------------------   --------------------

                                              FABS( )  ABSOLUTE VALUE
ELEMENTARY COMMANDS    ARITHMETIC SYMBOLS     FADC( )  ANALOG-DIGITAL
--------------------   --------------------   FATN( )  ARCTANGENT
                                              FCOS( )  COSINE
ASK                    ^  EXPONENTIATION      FDIS( )  DISPLAY
COMMENT                *  MULTIPLICATION      FEXP( )  EXPONENTIAL
CONTINUE               /  DIVISION            FITR( )  INTEGER
DO                     +  ADDITION            FLOG( )  LOG (BASE E)
ERASE                  -  SUBTRACTION         FRAN( )  RANDOM NUMBER
FOR                    () PARENTHESES         FSGN( )  SIGN PART
GO                     [] SQUARE BRACKETS     FSIN( )  SINE
GOTO                   <> ANGLE BRACKETS      FSQT( )  SQUARE ROOT
IF                                            FIN( )   CHARACTER INPUT
MODIFY                                        FOUT( )  CHARACTER OUTPUT
QUIT                   SPECIAL CHARACTERS     
RETURN                 --------------------
SET
TYPE                   !  RETURN/LINE FEED    MISCELLANEOUS
WRITE                  #  CARRIAGE RETURN     --------------------
                       :  TAB
                       %  OUTPUT FORMATTER    CHANGES FROM FOCAL 69
LIBRARY COMMANDS       $  SYMBOL TABLE        DEVICE NAMES
--------------------   "  QUOTATION MARKS     DIRECT COMMANDS
                       ?  TRACE               ERROR CODES
LIBRARY CALL           E  POWER-OF-TEN [&]    EXPRESSIONS
LIBRARY DELETE            RUBOUT KEY          FILES
LIBRARY GOSUB             CTRL/C              HIGH SPEED READER
LIBRARY LIST              CTRL/G [BELL]       INDIRECT COMMANDS
LIBRARY RUN               CTRL/L              INITIAL DIALOGUE
LIBRARY SAVE              CTRL/P (Stop Run)   LINE NUMBERS
LIBRARY EXIT              CTRL/Z              MERGING PROGRAMS
                          LINE FEED KEY       NAMES OF FILES
                       _  KILL LINE           PRECISION
FILE COMMANDS             RETURN KEY          PIP
--------------------      ALT MODE KEY        PUSHDOWN LIST OVERFLOW
                          SPACE KEY           SAMPLE FILES PROGRAM
OPEN INPUT             ,  COMMA               SIZE OF PROGRAMS
OPEN OUTPUT            ;  SEMICOLON           STRINGS
OPEN RESTORE INPUT                            SUBSCRIPTING
OPEN RESTORE OUTPUT                           SUMMARY OF COMMANDS
OUTPUT CLOSE                                  TAB
EXAMPLE                                       VARIABLES



   (A COPY OF THE 'HELP' PROGRAM IS SAVED UNDER THE NAME 'HELP.RE')
Example of running help

Help on other languages and links to main help



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