"U
The object-oriented paraUML has been applied to countless domains, including: 
Banking and investment sectors 
Health care 
Defense 
Distributed computing 
Embedded systems 
Retail sales and supply"
"

"worker responsibilities (swim lanes)"

I don't really understand why someone would actually go through the effort of learning UML.....

"A use case must be initiated by an actor."

"
and the second consists of: 
    StepA 
    StepB 
    StepC 
they can be merged into: 
    Step1 
    StepA 
    StepB 
    Step2 
    StepC 
    Step3 
but not into: 
    Step1 
    StepB 
    Step2 
    StepA 
    Step3 
    StepC  
"