Why is SRS also known as the black box specification of system?

Related questions

1. What is user characteristics in SRS?
2. What are the advantages of SRS?
3. What is the difference between FSD and BRD?
4. What is difference between FRS and SRS?
5. What is SRS What are the components of SRS?
6. What goes in a BRD?
7. What is the meaning of SRS?
8. Who writes the software requirement specifications document SRS?
9. What is SRS and characteristics of SRS?
10. What is the difference between business requirement and functional requirement?

Tags

1. #developed
2. #system
3. #visible
4. #document
5. #reason
6. #called
7. #externally
8. #black
9. #specification
10. #behavior
11. #specify
12. #should