| assign | Assign a new value to a control variable. |
| break | Terminate loop execution. |
| comment | Add a comment of one line to the program. |
| continue | Skip the current loop execution. |
| else | Alternative of conditional statement. |
| elseif | Conditional statement with alternative. |
| endfor | End of for loop. |
| endif | End of if command. |
| endwhile | End of while loop. |
| exit | Terminate HDevelop. |
| for | Execute the body for a fixed number. |
| if | Conditional statement. |
| ifelse | Conditional statement with alternative. |
| insert | Assignment of a value into a tuple. |
| repeat | Start of repeat..until loop. |
| return | Terminate procedure call. |
| stop | Stop program execution. |
| until | Continue to execute the body as long as the condition is not true. |
| while | Continue to execute the body as long as the condition is true. |