The Library of Congress Subject headings comprise a thesaurus of subjected headings maintained by the United States Library of Congress, for use in bibliographic records. They are applied to every item within a library’s collection, and facilitate a user’s access to items in the catalogue that pertain to similar subject matter. You can use them in "subject' searches.

Film Noir.

Film noir -- Catalogs.

Film noir -- United States -- History and criticism.

Film noir -- History.

Film noir -- History and criticism.

Film noir -- History and criticism.

Film noir -- Social aspects.

Film noir -- United States.

Film noir -- United States -- Encyclopedias.

Film noir -- United States -- History.

Film noir -- United States -- History and criticism.

Film noir -- United States -- Reviews.

Film noir -- United States -- Review

Jazz in motion pictures

Spy stories, American-- History and criticism.

American fiction --20th century--History and criticism.

Popular Literature--United States--History and criticism.

Literature and society--United States--History--20th century.

Detective and mystery stories, American --History and criticism.

Motion pictures--United States-- History and criticism.

Fantasy Fiction--American-History and criticism.

Run over the title to see a description of the site!

UTube user generated video on some of the elements of film noir. The beep in the beginning is part of the video! 

Many search engines, including Google and WorldCat, use Boolean logic. Here how to get the most out of your search:

How to use Boolean logic:

Boolean logic refers to a logical rather than an arithmetical operation set. Boolean logic is used in many search engines and indexes including Google.

AND: Unlike arithmetical operation sets, using "and" in Boolean logic makes your results smaller. For example, if you were to type "geese" and "ducks" you WOULDN'T get all the sites with geese and ducks alone or together, BUT ALL THE SITES THAT MENTION BOTH GEESE AND DUCKS.  And means:

If (ducks) is true (present in the record)

AND (at the same time in the same record)

If (geese) is true

OR: In common parlance "or" means either I'll have an orange or a banana. But not both. In Boolean logic "or" retrieves all the banana records plus all the orange records. OR=MORE

If (banana) is true (present in the record)

OR

If (orange) is true (present in the record) 

Retrieve the record

NOT: Like "and," using "not" reduces and refines your search. 

If (rivers) is true (present in the record)

And

If (lakes) is NOT true (not present in the record)

Retrieve the record

Other Tips:

Parentheses: the expression in parentheses will be evaluated first. Thus, ducks NOT migration OR geese is the same as (ducks NOT migration) OR geese

Controlled Vocabulary: Use library of congress subject headings in your search. In addition, look for the thesaurus, descriptors, authority control pages in many indexes which will show you what vocabulary to use when searching in their database.