Classification by Precision Level
Standard Consumer Grade
Precision: Error margin of approximately ±0.1 to ±0.5 seconds; utilizes standard quartz crystal oscillators.
Typical Use Cases: Daily study, kitchen cooking, general office timing.
Professional High-Precision Grade
Precision: Error margin as low as one ten-millionth of a second (e.g., quantum timers).
Typical Use Cases: Sports events (e.g., the Olympics), industrial precision testing, scientific research experiments.
Classification by Power Supply Method
Battery-Powered Models
Types: Coin cells, AAA batteries, etc.; battery life of 6–8 months.
Features: Portable and free from wiring constraints; suitable for desktop use or carrying on the go.
Type-C/USB Rechargeable Models
Features: Supports recharging; some models can provide power to other small external devices.
Typical Use Cases: High-frequency usage scenarios such as office work or photography.
