**Explanation:**

A rectangle is a four-sided polygon with opposite sides that are equal in length and four right angles. It is a special type of parallelogram. One of the key features of a rectangle is that it has two pairs of parallel sides.

**Lines of Symmetry:**
A line of symmetry is a line that divides an object into two congruent halves that are mirror images of each other. In other words, if you were to fold the object along the line of symmetry, both halves would perfectly overlap.

**Symmetry in a Rectangle:**
To determine the number of lines of symmetry in a rectangle, we need to examine its properties.

1. **Vertical Line of Symmetry:**
- A rectangle has one vertical line of symmetry that divides it into two congruent halves.
- If you were to fold the rectangle along the vertical line of symmetry, both halves would overlap perfectly.

2. **Horizontal Line of Symmetry:**
- Similarly, a rectangle also has one horizontal line of symmetry that divides it into two congruent halves.
- Folding the rectangle along the horizontal line of symmetry would result in perfect overlap of both halves.

3. **Combining Vertical and Horizontal Symmetry:**
- When the vertical and horizontal lines of symmetry are combined, they intersect at the center of the rectangle.
- This point is the point of symmetry for both lines.

4. **Diagonal Lines of Symmetry:**
- A rectangle does not have any diagonal lines of symmetry.
- Folding the rectangle along any diagonal line would not result in perfect overlap of the halves.

Therefore, a rectangle has a total of **two lines of symmetry** - one vertical and one horizontal. These lines divide the rectangle into four congruent quadrants.