A lot of content does not require release forms. However, for content aimed at commercial publication and use, Model Releases are required for any individual that is depicted or individually recognizable, like an actor/actress, as long as this constitutes the main bulk of the footage in question.

Similarly, where an individually recognizable property constitutes the main content depicted, including trademarks, artworks, brands and logos, a Property Release is required.

Please take care to use a model release when appropriate, and if you are in doubt it is better to opt for safety. You can find a copy of a standard model and property release forms here.