The area of a rectangle is calculated using the formula:

$\text{Area} = \text{Length} \times \text{Width}$

Given that the length is 12 inches and the width is 4 inches, we can substitute these values into the formula:

$\text{Area} = 12 \, \text{in} \times 4 \, \text{in} = 48 \, \text{square inches}$

Thus, the area of the rectangle is 48 square inches.

Would you like further details on how to calculate the area, or do you have another question? Here are some related questions you might find interesting:

1. How does the area of a square differ from that of a rectangle?
2. What are the properties of rectangles that affect their area?
3. How do you calculate the perimeter of a rectangle?
4. How can the area of irregular shapes be calculated?
5. What is the relationship between area and scale in geometric shapes?

Tip: Always double-check the units used when calculating area to ensure they are consistent (e.g., both in inches or both in centimeters).