update README with info and sightings, add the program

MATRIX

@@ -0,0 +1,33 @@
+ 1 REM THE MATRIX
+ 5 FOR I = 1 TO 30: PRINT " ": NEXT I
+ 10 DIM K(3,2)
+ 11 H = 0
+ 12 V = 1
+ 13 F = 2
+ 15 FOR C = 0 TO 3
+ 16 GOSUB 50
+ 17 NEXT C
+ 20 FOR C = 0 TO 3
+ 30 R =  INT ( RND (1) * 20)
+ 31 IF R = 1 THEN  GOSUB 50
+ 32 IF R >< 1 THEN  GOSUB 100
+ 35 NEXT C
+ 39 GOTO 20
+ 50 REM  RESET
+ 51 K(C,H) =  INT ( RND (1) * 40)
+ 52 K(C,V) = 0
+ 53 K(C,F) =  INT ( RND (1) * 2)
+ 99  RETURN
+ 100 REM  DRAW
+ 101 K(C,V) = K(C,V) + 1
+ 102 IF K(C,V) > 20 THEN  RETURN
+ 103 VTAB K(C,V): HTAB K(C,H)
+ 110 IF K(C,F) = 1 THEN  GOSUB 120
+ 111 IF K(C,F) = 0 THEN  GOSUB 130
+ 119 RETURN
+ 120 REM  DRAW CHAR
+ 121 PRINT  CHR$ ( INT ( RND (1) * 96 + 32))
+ 122 RETURN
+ 130 REM  ERASE CHAR
+ 131 PRINT " "
+ 132 RETURN

README.md

@@ -1,4 +1,24 @@
 apple-ii-matrix
 ===============
 
-A BASIC program that produces a Matrix-like display on Apple II computers
+A BASIC program that produces a Matrix-like display on Apple II computers.
+
+To get this running on your machine, you need to get to the Apple's BASIC prompt, and then
+type in the lines as shown. There is no text editor; simply typing in a line preceded by a number
+adds it to the program buffer. Then type RUN.
+
+
+history and sightings
+=====================
+
+I first created at Vancouver Mini Maker Faire, in June 2012. I saw an old Apple II running a lacklustre demo and I decided
+to bust out some quarter-century old skills. The owner of the machine graciously let me use it for a half hour or so, and
+with the help of some other bystanders we got this:
+
+http://www.flickr.com/photos/brevity/7429579820/
+
+Next, I saw an Apple II at Panic Software in Portland, during the XOXO Festival in September 2012, and decided to 
+type it in. It's been photographed by a number of people since then, including Scott Beale of Laughing Squid:
+
+http://www.flickr.com/photos/laughingsquid/8047518696/
+http://instagram.com/p/QSVgQkAT6H/