The number line in the image shows an open circle at $0$ and an arrow pointing to the left towards negative numbers.

An open circle means that $0$ is not included in the solution. The arrow pointing to the left indicates that the inequality involves numbers less than $0$.

Therefore, the inequality represented by this number line is: $x < 0$

Would you like more details or have any questions?

Here are some related questions to expand on this topic:

1. What does a closed circle on a number line represent?
2. How do you represent $x \geq -2$ on a number line?
3. What does it mean if an inequality has a “greater than or equal to” sign?
4. How do we solve a linear inequality?
5. What are the different ways to graph inequalities on a coordinate plane?

Tip: Remember, an open circle on a number line means the number at that point is not included, while a closed circle means it is included.