WordPress has an in-built image gallery feature incredibly simple to use. So let’s say you are writing a post that you want to include an image gallery in.
The Media Library SubPanel allows you to edit, view, and delete Media previously uploaded to your blog. Multiple Media objects can be selected for deletion. Search and filtering ability is also provided to allow you to find the desired Media. If you do need to upload Media, even if that Media is not related to a Post or Page, then you need to use the Media Add New SubPanel.