A title slate is simply text on-screen and nothing else. Slates are using to introduce scenes into your video should they be necessary.
Sometimes the only slates you need is at the beginning (such as stating the title of the video) and at the end (for credits). At other times you may need slates during the video to separate different chapters. For example, if you were producing an instructional video that showed a 5-step process on how to do something, each one of those 5 steps would most likely need a title slate to introduce each step.

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