Zend Studio allows you to easily manage and install external PHP libraries used for running applications in your development environment. These libraries can be anything from a family of files or functions, to fully structured feature-rich frameworks (e.g., Zend Framework 2). External PHP libraries are not deployed automatically together with the project, but can be deployed separately on your application server. Libraries can also be imported as .zpks. and then consumed later in your PHP projects.
Folders containing PHP library code that is developed and deployed as part of your project but not actively maintained, can be flagged as Library Folders.
As such, they are not automatically validated together with the source code of the project, meaning that syntax errors in the code will not appear in your Problems view. Additionally, Zend Studio automatically flags libraries installed in a project's 'vendor' folder as Library Folders (e.g., in a Composer-enabled project).
Deploying libraries can only be performed on Zend Server 6.1 and above.