INKEY$ reads the keyboard and returns a single character if an input is pending on the keyboard.
A$ = INKEY$
10 A$ = INKEY$ 20 IF A$ = "" THEN 40 30 PRINT A$ 40 GOTO 10
If a key has not been pressed then a null string is returned. The ASCII code of each key, including control codes, is read and assigned to the one character string variable A$.
The characters entered into the program in this manner are not displayed on the screen unless explicitly printed (line 30 in the example). One application may be to insert a pause in a program before displaying another screen of information:
80 PRINT"last line of last screen" 90 A$=INKEY$: IF A$="" then 90 100 PRINT"First line of next screen"
If a function key is pressed then a two character string is returned consisting of the character '^' and the number of the key pressed i.e. Pressing Function Key 1 will return the string "^1" to an INKEY$ function.