What is Ethernet over Coax and how does it make my WiFi better?

I bought a router with a coaxial input for my apartment, however

What is Ethernet over Coax and how does it make my WiFi better?

Passive adapter for Ethernet transmission over a coaxial cable. Compatible with point-to-point or home-run cabling only. Transmission distance up to

Ethernet Over Coax EOC Adapter Kit (DECA-100) - Twin Pack - by PAIRTEK

Coax Cable to Ethernet Adaptor, GCA-2000-KIT For Sale

What is Ethernet? Everything You Need to Know About Wired Networks

Comtrend Launches G.hn Wave 2 Ethernet Over Coax Adapter for

Coax Cable to Ethernet Adaptor, GCA-2000-KIT For Sale

Ethernet Over Coax Adapter TRENDnet - TRENDnet TMO-311C

ScreenBeam Bonded MoCA 2.0 Network Adapter for High Speed Internet

Ethernet Over Coax - Speedy !!