File provides two node types for managing packages of files. Either type can be used for file nodes and normal nodes, for image files and non-image files, and both support the node maintance operations (edit, copy, move, delete). File package may make more sense where there are few images, and gallery package when there are many images.
File Package provides a basic upload and listing capability.
Gallery Package provides an upload and image preview capability.
The gallery package uses the File With Derivatives node type to create file nodes which automatically create preview images. The preview images use their main image as a package, and you will need to manage permissions (for example, with a Permission Manager) to make sure that these are visible.
The gallery package does not resize the main images. Many solutions will need to set maximum image sizes, and will need to create their own member types for this. See File member type types for more details.