Definition - What does Deprecated mean?
Deprecated refers to a software or programming language feature that is tolerated or supported but not recommended. A deprecated attribute or feature is one that may eventually be phased out, but continues to be used in the meantime. Deprecation also helps to ward off backward compatibility issues, giving users time to migrate and begin using the newer recommended feature. The deprecated feature will continue to work in the current environment, but will show a warning message that the feature being used may be removed in future releases.
Techopedia explains Deprecated
A deprecated feature is normally replaced by a superior feature with additional functions. A software feature may be deprecated for various reasons, for example, HTML once included a FONT element to allow users to select the text font style of their choice. When CSS and HTML 4.0 were introduced, the FONT element was deprecated.