A dot marked on a paper represents a point.

Answer

**Step-by-Step Solution:**

1. **Understanding the Concept of a Point**: A point is a fundamental concept in geometry. It represents a specific location in space but does not have any dimensions (length, width, or height).

2. **Representing a Point**: To illustrate a point, we can mark a small dot on a piece of paper. This dot serves as a visual representation of the point.

3. **Characteristics of a Point**: The dot we draw has no size; it is simply a mark that indicates a position. Therefore, we can conclude that a point is an exact location in a geometric space.

4. **Notation**: In geometry, points are often labeled with capital letters (e.g., Point A, Point B) to distinguish them from one another.

5. **Conclusion**: Thus, a dot marked on a paper is a representation of a point, which is a basic element in geometry.

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