With agile development, the product is created in short cycles — iterations — in close cooperation of all team members and, importantly, users.
There are no consecutive stages where the participants of stage 3 wait for stage 1 to be completed, and then 2. All stages — 1, 2, 3, etc. — are run in parallel. Thanks to this, the user can get a working prototype of the final product almost at the very beginning of the project.
The most well—known concepts of agile development in the world are kanban and scrum.