Active learning is a type of learning approach. It is an interactive approach where the machine constantly learns but requires human input for things it struggles with. An active learning system is also known as a ‘human-in-the-loop’ system. The model knows which data points it struggles with so actively prompts the human for help.
Once the human provides input, the model learns from this new data and improves. There is a continuous feedback loop between the human and the machine so the model improves over time with human interaction.