human: What are the information resources available on the USPTO Office of Patent Classification (OPC) site?
assistant: Information resources available on the USPTO Office of Patent Classification (OPC) site are:
The Cooperative Patent Classification (CPC) scheme and definitions. For Cooperative Patent Classification (CPC) frequently asked questions (FAQ) and training related information, please visit the bi-lateral CPC information page (link is external)or start browsing the CPC scheme. 
The United States Patent Classification (USPC) schedules, definitions, and the Index to the USPC. For information about USPC (e.g., Patent Examiner's Handbook for USPC, etc.) please browse the USPC resources section and the Documents and Reports related to the USPC Manual of Classification on the Classification Standards and Development Home Page.  
The International Patent Classification (IPC) scheme, definitions, and catchword index. For information about IPC (e.g., IPC Guide, Nice Agreement, Locarno Agreement, etc.) please visit the International Classification Resources page on this site.