HDMI stands for High Definition Multimedia Interface. HDMI connectors are used to link laptops to monitors, DVD/Blu-ray player to TV, set-top boxes like Apple TV, Roku to TV,and much more. Majority of the computer monitors out there have at least two HDMI ports. Newer computer monitors (manufacturerd after 2014) most likely would have a HDMI port along with DP (Display Port) a VESA standard. 

USB Type-C ports can be found on almost any devices these days from simple external hard drives to high-end laptops and the latest smartphones. Almost all Macs and Windows laptops now featuring the interface.