LibGuides are websites - put together by librarians - that focus on particular topics. While some (much) of the content may be restricted to a particular campus or library - many LibGuides will also list free (open access) materials under categories such as "internet resources" - "websites" - "digital collections" - "digital libraries".
If I was looking for digital archives on the history Native Americans I might try various Google searches such as:
Here are a few of the most useful and heavily used Google search commands:
"quotes" putting words in quotes will lock in a phrase
e.g. the Google search: "North Carolina" will look for that exact state
the Google search: North Carolina
might find North Dakota and South Carolina
intitle: looks for a particular word or phrase (but not all words) in the title of the website
e.g. LibGuide intitle:"civil war"
This search looks for "civil war" in the title but not the word LibGuide
e.g. "digital archive" intitle:slavery
This search looks for slavery in the title of the website but not the phrase "digital archive"
Be sure the word or phrase is immediately adjacent to the command intitle: (no spaces)
This command should be typed in lower case letters.
site: this command limits to websites from a particular site or domain
e.g. "digital collections" "great awakening" site:.edu
This search limits results to college and university websites (.edu)
e.g. "digital archives" intitle:abolition site:.gov
This search limits results to local, state, and federal government websites (.gov)
Be sure the word or phrase is immediately adjacent to the command "site:" (no spaces)
The "site:" command can also be used to search the website of an organization. To do this find the organization online - e.g. New York Public Library - and take the root of the URL (web address) - the part after the "www" and before the first slash "/"
e.g. http://www.nypl.org/collections use "nypl.org" in the command
e.g. "digital collection" abolition site:.nypl.org
To search the webpages of the United Nations - find a web address of the United Nations - http://www.un.org/en/ - and use the root of this web address - "un.org"
e.g. "digital library" slavery site:un.org