Used when loading time is unknown. It can be default spinners, creative indeterminate indicators, animations showing that your app is “doing something” under the hood.
If a spinner is triggered by a button, place the spinner in the button, and disable the button while the spinner is visible.
If only a specific section of a page is loading new content or being updated, place the spinner in that section of the page.
You should only show a spinner if the expected wait time is more than a second. (Keep in mind that most hospitals have slow internet speed).
As a general rule, you should use this type of progress indicator for fast actions (2–10 seconds). Making the user stare at a spinning wheel or infinite linear animation longer can increase bounce rates for your website or cause people to close your app.