Employs mathematical notation and proof techniques to specify and verify software.

Advantages: High reliability, reduces ambiguity, strong error detection.

Disadvantages: Requires specialized skills, high cost, not suitable for all projects.

Unified Process (UP):

Iterative and incremental, use-case driven, architecture-centric, and risk-driven.
Phases: Inception, Elaboration, Construction, Transition.
Workflows: Business Modeling, Requirements, Analysis & Design, Implementation, Test, Deployment.
Advantages: Strong emphasis on architecture and risk, good for large teams.
Disadvantages: Can be complex, heavy documentation.

2.3 Agile Development

Agile Manifesto: Individuals and interactions over processes and tools; Working software over comprehensive documentation; Customer collaboration over contract negotiation; Responding to change over following a plan.
Principles: Early and continuous delivery, welcoming change, frequent delivery, close daily cooperation, motivated individuals, face-to-face conversation, working software, sustainable development, technical excellence, simplicity, self-organizing teams, regular reflection.
Advantages: Flexibility, quick response to change, increased customer satisfaction, higher quality.
Disadvantages: Less documentation, can be challenging in large organizations, requires active customer involvement.

2.4 Specific Agile Methodologies

Extreme Programming (XP):
- Values: Simplicity, Communication, Feedback, Courage, Respect.
- Practices: Pair programming, Test-Driven Development (TDD), Continuous Integration, Small Releases, Refactoring, Collective Code Ownership, On-site Customer.
Feature-Driven Development (FDD):
- Process: Develop Overall Model, Build Feature List, Plan By Feature, Design By Feature, Build By Feature.
- Focus: Short iterations driven by "features" (small, client-valued functions).
Lean Software Development:
- Principles (from Lean manufacturing): Eliminate Waste, Amplify Learning, Decide as Late as Possible, Deliver as Fast as Possible, Empower the Team, Build Integrity In, See the Whole.
Scrum:
- Roles:
  - Product Owner: Defines product vision, manages Product Backlog.
  - Scrum Master: Facilitates Scrum process, removes impediments.
  - Development Team: Self-organizing, cross-functional, develops the increment.
- Events (Ceremonies):
  - Sprint: Time-boxed iteration (typically 1-4 weeks).
  - Sprint Planning: Team selects items from Product Backlog for the Sprint Backlog.
  - Daily Scrum (Stand-up): Short daily meeting to synchronize activities.
  - Sprint Review: Team presents completed work to stakeholders.
  - Sprint Retrospective: Team inspects and adapts its process.
- Artifacts:
  - Product Backlog: Prioritized list of all desired features.
  - Sprint Backlog: Subset of Product Back