UML activity diagram - Ticket processing system

"An issue tracking system (also ITS, trouble ticket system, support ticket, request management or incident ticket system) is a computer software package that manages and maintains lists of issues, as needed by an organization. Issue tracking systems are commonly used in an organization's customer support call center to create, update, and resolve reported customer issues, or even issues reported by that organization's other employees. An issue tracking system often also contains a knowledge base containing information on each customer, resolutions to common problems, and other such data. An issue tracking system is similar to a "bugtracker", and often, a software company will sell both, and some bugtrackers are capable of being used as an issue tracking system, and vice versa. Consistent use of an issue or bug tracking system is considered one of the "hallmarks of a good software team".
A ticket element, within an issue tracking system, is a running report on a particular problem, its status, and other relevant data. They are commonly created in a help desk or call center environment and almost always have a unique reference number, also known as a case, issue or call log number which is used to allow the user or help staff to quickly locate, add to or communicate the status of the user's issue or request.
These tickets are so called because of their origin as small cards within a traditional wall mounted work planning system when this kind of support started. Operators or staff receiving a call or query from a user would fill out a small card with the user's details and a brief summary of the request and place it into a position (usually the last) in a column of pending slots for an appropriate engineer, so determining the staff member who would deal with the query and the priority of the request." [Issue tracking system. Wikipedia]
The UML activity diagram example "Ticket processing system" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Rapid UML solution from the Software Development area of ConceptDraw Solution Park.

This example of UML class diagram models bank account system.
"A bank account is a financial account between a bank customer and a financial institution. A bank account can be a deposit account, a credit card, or any other type of account offered by a financial institution. The financial transactions which have occurred within a given period of time on a bank account are reported to the customer on a bank statement and the balance of the account at any point in time is the financial position of the customer with the institution. a fund that a customer has entrusted to a bank and from which the customer can make withdrawals." [Bank account. Wikipedia]
This bank account system UML class diagram example was created using the ConceptDraw PRO diagramming and vector drawing software extended with the ATM UML Diagrams solution from the Software Development area of ConceptDraw Solution Park.