Toast is a lightweight push notification used to provide hints to the users for the consequence of any user actions (eg. Form submission, Notification alert messages and etc.) Default Toasts have two parts basically, one is the header ( .toast-header ) and another is the body ( .toast-body ) which contains the actual message. See the Pen Bootstrap 5 Toasts by Prime Study Hub ( @PrimeStudyHub ) on CodePen . Colorful Toasts You can change the background color of the Toasts by using the Bootstrap 5 background utilities (eg. .bg-primary , .bg-secondary , .bg-info , .bg-danger , etc...). See the Pen Bootstrap 5 Colorful Toasts by Prime Study Hub ( @PrimeStudyHub ) on CodePen .