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Now run it. You will see the headings printed on the screen by line 20, but what happened to line 10? Apparently the computer has completely ignored it changing its colour to red. Indeed, **REM** in line 10 stands for REMark and is there solely to remind you of what the program does. A **REM** command consists of **REM** or the semicolon symbol ( **;** ) followed by anything you like, and the computer will ignore it right up to the end of the line.

**REM** is not really part of a *NextBASIC* program, it just adds remarks to it for improved readability and documentation and gets totally ignored by *NextBASIC*. For example:

<pre><code>10 <span data-colour="red">REM this is a remark</span>
20 <span data-colour="red">; This is also a remark</span>
</code></pre>

are functionally equivalent, as are:

<pre><code>10 PRINT 10:<span data-colour="red">REM Remark</span>
20 PRINT 20:<span data-colour="red">; Remark</span>
</code></pre>

Note that the colon (:) cannot be ommited, like:

<pre><code>10 PRINT 10;<span data-colour="dark blue">Remark</span>
</code></pre>

as then **Remark** forms part of the **PRINT** statement. A colon must ALWAYS be used to separate statements on the same line.

### Using STOP, BREAK and CONTINUE

By now, the computer has got to the **INPUT** command on line 40 and is waiting for you to type in a value for the variable **F** – you can tell this because at the bottom of the screen is a flashing cursor. Enter a number; remember to press **ENTER** afterwards! Now the computer has displayed the result and is waiting for another number. This is because of line 60, **GO TO @inpF**, which means exactly what it says. Instead of running out of program and stopping, the computer jumps back to line 40 where the label **@inpF** is located and starts again. So, enter another temperature. After a few more of these you might be wondering if the machine will ever get bored with this, it won't. Next time it asks for another number, enter the word **stop**. The computer will stay in the line and the cursor will change shape indicating a non acceptable entry. You have there the choice of hitting **BREAK** in which case you receive a report **H STOP in INPUT, 40:2**, which tells you why it stopped, and where (in the second statement of line 40, first being the label **@inpF**).

If you want to continue the program type:

```
CONTINUE
```

and the computer will continue with the **INPUT** line.

There's a synonym of **CONTINUE** which is really there for convenience and it's **CONT**. Try it in lieu of **CONTINUE** above; it will work in the same way.

Replace line 60 by **GO TO 21** – it will make no perceptible difference to the running of the program. If the line number in a **GO TO** command refers to a non-existing line, then the jump is to the next line after the given number.

This, however, is NOT the case when using **GO TO** to jump to a *label* as the latter MUST exist otherwise an error will be produced. The same allowance for line numbers is true as well for **RUN**; in fact **RUN** on its own actually means **RUN 0**.

Now type in numbers until the screen starts getting full. When it is full, the computer will move the whole of the top half of the screen up one line to make room, losing the heading off the top. This is called scrolling.

When you are tired of this, stop the program as shown above and get the listing by pressing **ENTER**.