Portal has following variations of buttons.
Primary Button
Primary buttons are used for primary actions in a scenario. We often use a primary button to draw attention to a page’s highest priority action, such as “Add to Bag” or “Submit”. Primary buttons should be visually prominent and be limited to 1 per page. They can be used in isolation or in conjunction with a Secondary or Tertiary CTA.
Secondary Button
Secondary buttons are similar to the Primary button, but intended to play a more supportive or less important action button role. They are used in situations where there are multiple call to actions present and can be used in isolation or in conjunction with a Primary or Tertiary CTA. Ex: Consider using the Secondary button style for things like “Edit”
Tertiary Button/Links
For less prominent, and sometimes independent, actions. Tertiary buttons can be used in isolation or paired with a primary button when there are multiple calls to action. Tertiary buttons can also be used for sub-tasks on a page where a primary button for the main and final action is present.
Icon Buttons
Icon button is a type of button where developer can add any icon from prime faces, which will look as a button.
Split Buttons
Split button is a type of button where a button is split into two parts with a drop down to provide options.