HDMI-switch AV-Connection

What is the function of the HDMI cable?

Lindy 2-way HDMI 2.1 switch with remote control

Denon 8K HDMI Switcher model AVS-3

3-way HDMI switch with cable (3 in -1 out)

av:Link 3:1 HDMI Switcher - Trax Music Store

Hdmi Rca Converter Audio, Av Hdmi Converter, Hdmi Rca Vention

Lindy HDMI 2.0 splitter with HDR (1 in - 2/4/8 out)

AS-HDM-5X1SW - HDMI Switches - AV Distribution - A/V Accessories & Hardware - MHTG

New 8K KVM Switch with HDMI 2.1 for Gaming