What are the main stages characterized by the process of developing software systems?

The process of developing software systems typically includes several main stages:

1. Requirements analysis — gathering and clarifying customer requirements, understanding the tasks the system should solve.
2. Design — creating the system architecture, selecting technologies, developing data structures and interfaces.
3. Implementation (coding) — writing the source code according to the design.
4. Testing — verifying functionality, finding and fixing bugs.
5. Deployment — deploying the system in a production environment.
6. Support and maintenance — fixing bugs, updates, improving functionality.

These stages can be performed sequentially (waterfall model) or iteratively (agile methodologies, for example, Agile).