Dialogs
A dialog is a small window that prompts the user to make a decision or enter additional information. A dialog does not fill the screen and is normally used for modal events that require users to take an action before they can proceed.
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Toasts
A toast provides simple feedback about an operation in a small popup. It only fills the amount of space required for the message and the current activity remains visible and interactive. For example, navigating away from an email before you send it triggers a "Draft saved" toast to let you know that you can continue editing later. Toasts automatically disappear after a timeout.
The main diff is that Dialog can take input from user and displays some msg,,,, but Toast mainly used to pop up message,,,, and parent activity will be visible in both cases.. :)
