input: [Library Catalog] Employs a Google-like free text keyword search. You can use the Advanced Search or command codes to search by fields (author, title, or subject). For assistance, see the WorldCat help page. [Classic Catalog] Depends on "fielded searches." You choose what element of the record (author, title, subject, call number, etc.) to search. [0] 
output: How does the basic search work?