Unified Modeling Language (UML)

UML is an industry standard modeling language which uses visual diagrams and elements to create software documentation and design. 

Build detailed UMLmodels.
Manage project complexity.
Reverse engineer legacy code and database schema.
Produce reports.
Track changes
Involve the whole design team.


UML defines following diagrams 
Package diagrams
Class or Structural diagrams
Object diagrams
Composite Structure
Component diagrams
Deployment diagrams
Use Case Diagrams
Activity diagrams
State Machine diagrams
Communication diagrams
Sequence diagrams
Timing diagrams
etc.


UML used in scientific and business worlds. The UML is a tool for specifying software systems. Standardized diagram types to help you describe and visually map a software system's design and structure. UML is independent of target platform. UML is naturally oriented towards Object-Oriented programming.
The  UML is a tool for defining the structure of a system to manage large, complex systems. Building up libraries of UML Patterns simplifies the re-use of models and code.


UML defines the notation and semantics for the following domains:


Use Case Model - Describes boundary and interaction between the system and users. 


The Interaction Model - describes how objects in the system will interact with each other.


The State Model - Describe states /conditions of classes change over time. 


The Class Model - describes the classes and objects 


The Physical Component Model- describes the software and hardware components


The Physical Deployment Model - describes the physical architecture and the deployment of components on a hardware architecture.