Synthetic data is artificially generated data, often made by an AI, that replaces or supplements real data.
Example
Instead of real customer conversations, you generate 1,000 made-up sample chats to test a support bot.
For pros
It helps with rare cases, privacy and training smaller models. Risks: errors and biases of the generating model are copied, and training too much on AI data can degrade models. Synthetic data derived from real personal data can still relate to individuals.