: Technical "papers" in the form of installation guides and user manuals are typically available in the Download Center of the official ZKTeco website.
If you own a device like the U160 or K40, the trial or Lite version available via official distributors is an excellent start. Zkteco Biotime 8.5 Free Download
Includes a standard API for seamless integration with third-party HR and payroll systems. : Technical "papers" in the form of installation
The software is typically provided as a "free-to-download" package, though full activation usually requires a license. Zkteco Biotime 8.5 Free Download