The BPMN 2.0 Notation
BPMN 2.0 is a comprehensive process modeling notation with more than 150 shapes and connectors. Most companies never use all of them, so it's helpful to create a subset of the most frequently used process elements for easy access.
Focusing on the frequently used elements helps users avoid unnecessary complexity and focus on the best-suited notations for their processes. For example, if you're creating an end-to-end process, you can show your modelers only the elements that pertain to those types of processes.
You can change the default appearance of the notation elements, such as font type or color for tasks. These format attributes are defined for all notation subsets. For example, if you change the background color of the task element, the system changes all BPMN subsets accordingly.
Recommendation: Use light colors, so it does not affect readability. The image on the right shows how the bottom green and pink tasks are hard to read, while the grey and yellow are easier on the eyes.