Microsoft BASIC

The first BASIC interpreter that Microsoft sold was for the Altair 8800 in 1975. It soon became the most popular language for the 8-bit home computers that followed in the years after. The language has stayed remarkably consistent since the start - only adding new language features.

Characteristics of Microsoft BASIC

• IF statements allow the use of GOTO and GOSUB without THEN.

  10 IF 1=1 GOSUB 200
  

• For loops execute at least once.

  10 A=5
  20 FOR F = 100 TO 1 STEP 1
  30 A=A+1
  40 NEXT F
  50 PRINT F,A
  RUN
   101            6

• When an expression evaluates as true then the value is -1.
• It is possible to use MID$() to replace characters in a string.

  10 A$="12345678901234567890"
  20 MID$(A$,5,3)="XYZ"
  30 PRINT A$
  1234XYZ8901234567890