I think this is how most people started programming and is probably the great-grandfather of the “Hello World” program example that is in vogue at the moment.
10 PRINT "Hello! "; 20 GOTO 10
You would pop into your local computer store, go up to the nearest computer, type the program in, issue the RUN command (and if you’d put a rude word in the PRINT statement) you would literally RUN!
Two simple lines of code and some numbers. But what does it all mean?
Well, the code is written in a programming language called BASIC. BASIC is an acronym which stands for Beginners All Symbolic Instruction Code.
The program consists of two lines of instructions. Each line starts with a unique line number; the program is ordered by these line numbers so line 20 follows line 10. If I inserted a line 15, this would appears between the two lines entered.
Line numbering is important as computers will execute the instructions in a programme from top to bottom, unless they are told to do otherwise.
The previously mentioned RUN command instructions the computer to start the program from the top. So, the first thing the computer will do in this short program is output “Hello” on the screen.
The computer will then execute the next command. This instructs the computer to go back to line 10.
The output of this program is therefore a screen full of “Hello “.
Fairly simple, eh? They don’t call it BASIC for nothing. OK, let’s get cracking on with the next lesson on Variables…