Define the gravitational force .

Explanation

**Step-by-Step Solution:**

1. **Definition of Gravitational Force**: The gravitational force is defined as the force of attraction that exists between any two objects due to their masses.

2. **Understanding the Concept**: According to the law of gravitation, every object with mass attracts every other object with mass. This means that if you have two objects, say Object 1 with mass \( m_1 \) and Object 2 with mass \( m_2 \), they exert a gravitational force on each other.

3. **Example of Gravitational Attraction**: For instance, the Earth attracts us because both the Earth and we have mass. This attraction is what keeps us grounded on the Earth’s surface.

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