Morse code
| A | •− | N | −• | 1 | •−−−− |
|---|---|---|---|---|---|
| B | −••• | O | −−− | 2 | ••−−− |
| C | −•−• | P | •−−• | 3 | •••−− |
| D | −•• | Q | −−•− | 4 | ••••− |
| E | • | R | •−• | 5 | ••••• |
| F | ••−• | S | ••• | 6 | −•••• |
| G | −−• | T | − | 7 | −−••• |
| H | •••• | U | ••− | 8 | −−−•• |
| I | •• | V | •••− | 9 | −−−−• |
| J | •−−− | W | •−− | 0 | −−−−− |
| K | −•− | X | −••− | ||
| L | •−•• | Y | −•−− | ||
| M | −− | Z | −−•• |
Dots and dashes. The most common cipher there is.