EMZETT.Mouse
In short: A pointing device used to control a cursor on the screen — today usually optical (via a light sensor) and connected wirelessly or via USB.
In more detail: Specs for a mouse include DPI (dots per inch, sensitivity) and, for gaming mice, the polling rate, which determines how often per second the position is reported to the PC.
In Depth
Optical mice work with a small light sensor on the underside, which captures an image of the surface below several thousand times per second and computes the direction and speed of movement from the shifts between consecutive images — similar to a tiny, extremely fast camera. Older mechanical mice instead used a rolling ball with mechanical sensors, which was considerably more prone to dirt and wear.
The DPI figure (dots per inch) describes how many sensor points per inch of physical mouse movement are captured — a higher DPI number means the same physical hand movement produces a larger movement of the cursor on screen (higher sensitivity). The polling rate (in Hz), by contrast, states how often per second the current position is even reported to the computer at all — a higher polling rate reduces the perceived delay between physical movement and cursor response, which is especially noticeable in fast games. Wireless mice transmit their data either via Bluetooth or via a proprietary radio receiver, with the latter usually offering lower latency than Bluetooth.
Ergonomics and shapes
Besides pure sensor technology, mice differ greatly in shape and grip type: symmetrical mice (equally suited for left- and right-handed users) versus ergonomically shaped models (usually only for right-handed users, adapted to the natural hand position), as well as weight and size for different grip techniques (palm, claw or fingertip grip). With long daily use, the right fit can noticeably reduce strain on the wrist and fingers.
Extra buttons and software customisation
Many mice, especially in the gaming and productivity space, offer additional programmable buttons besides the standard click buttons and scroll wheel — manufacturer software can assign arbitrary functions to these buttons (keyboard shortcuts, DPI switching at the press of a button, macros). Some mice store these profiles directly in the mouse’s own internal memory, so they work across devices without needing to be reconfigured.