Here is how it works.
1. You sign up to be a contributor, prove your age and ID, and agree to a contract.
2. You study Adobe's rules and guidelines. You need to learn their rules about model releases, intellectual property, the kinds of image they will accept, and the quality they need. If you are not producing work of the quality of an experienced professional photographer, your work will be rejected with no hints or help; Adobe will not help or train new photographers, because there are enough experienced photographers making work for them today.
3. You submit your pictures. You choose keywords to help people searching, like "tree" or "flower".
4. Adobe review the pictures and make sure they are of the highest professional standard, are pictures they want, and have no legal problems. Maybe they accept some.
5. If your pictures are accepted they appear in Adobe Stock catalog. Adobe do not pay you yet.
6. If people find your pictures, they will pay from $1 to $10 to Adobe. Adobe will pay you 33% of this money, but not right away. The buyer may use the pictures in adverts, magazines, web pages etc. and may make millions of dollars with it.
7. The hope is that many people find your picture, and license it. Each one will pay.
That is it. You have a lot of competitors, the Adobe stock catalog is very large. For example, "flower" has 19,824,503 pictures already. "Tree" has 24,707,512 pictures already.
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