SharePoint Document Libary :
Document libraries are collections of files that you can share with team members on a Web based on Microsoft Windows SharePoint Services. For example, you can create a library of common documents for a project, and team members can use their Web browsers to find the files, read them, and make comments.Microsoft SharePoint comes with some pre-defined list and library definitions. These include: Announcement Lists, Blogs, Contacts, Discussion Boards, Document Libraries, External Content (BCS) lists, Pages, Surveys, and Tasks.
Libraries allow you to set up templates for common types of document and also give the option of version control so that you can track any revisions.
SharePoint List :
A List can be thought of as a collection of pieces of information — all of which (typically) have the same properties. For instance, you can have a list of links called "my links", where each item has a name, and a description.Technically lists also include libraries, but libraries are often seen as separate from lists or at least specialized forms of lists. In lists items are defined by metadata or the columns of a list with documents being attached to that metadata. In a library a document is the item with library metadata supporting the document.
Lists have many features such as workflows, item-level or list-level permission, version history tracking, multiple content-types, external data sources, and many more features. Some of these features depend on the version of SharePoint that is installed.
To summarize for List :
1. It is best thought of as mini-databases.
2. A list will allow you to store a number of items such as KPIs, tasks, events,
staff details etc. in a similar way to how MS Excel or MS Access will.
3.The beauty of SharePoint's lists, is that you can make quick work of building a
simple database (with its own, customizable, data entry forms) in a matter of
minutes and without any coding. You can also choose which fields to include
(title, reference number, status, date etc.) or create your own by creating a
new content type and then adding custom columns to it.