a configurable view of data in a list
Every SharePoint list or library has at least one view associated with it(All items view in list). The view is a live, customizable display of the list items stored in the list. We can create SharePoint List views using browser and SharePoint Designer. You can perform basic list view customization, like filtering, changing the sort order, and showing or hiding columns.
You can create custom views of libraries and lists to organize and show items that are most important to you (like certain columns), to add filtering or sorting, or to have a more engaging style. You can create a personal view (that only you can see) or, if you have permissions to do so, you can create a public view for everyone who uses the list to see.
You can read more about the views in sharepoint, here.