How does a reverse image search work?

Related questions

1. How do you search an image from your camera roll?
2. How can you use a picture to search?
3. Can you reverse image search an Instagram photo?
4. Can I google search with a picture?
5. How do I search an image online?
6. How do you find out where a picture was taken?
7. Can I image search from my phone?
8. Can you take a picture of something and search it?
9. How can I identify something in a picture?

Tags

1. #submitted
2. #search
3. #picture
4. #feature
5. #reverse
6. #images
7. #advanced
8. #constructing
9. #model
10. #accomplishes
11. #allows
12. #mathematical
13. #users
14. #analyzing
15. #uploading
16. #related
17. #using
18. #google
19. #algorithms
20. #image