USB C is capable of usb 3 and higher speed and functions. The benefit of usb c over regular usb is that usb c can charges stuff a lot faster (if the port supports quick charging and the like), usb c to usb c can allow you to use a tablet with full battery to charge another device like a phone, and more. USB c is honestly going to change a lot of thing for computing as it gets adopted more and more. For example, you can have a single usb c connecting a monitor with built in usb hub to a computer and not need a power cord for the monitor. I have a MSI portable screen with mini HDMI for certain stuff, and it have two usb c so I can connect most any usb c devices to it and both power and drive the screen at the same time with a lot less cable clutters.
It's just way more versatile than the older usb ports now. Regarding 'apple port with lightning symbol', it's a little weird. Apple computers have thunderbolt usb c which is just a standard to provide a lot of functions via a single usb c cable (like the monitor example above). Apple also have a port called lightning which are NOT usb C. It looks similar but aren't all that great and obviously the propriety aspect of that port just sucks. There have been rumors for years that iPhones could switch over to usb c soon. It's honestly looking possible within the next couple years. Pretty much all modern phones nowadays have usb c, same for modern tablets and everything else. I have a usb c ereader, android phone with usb c, ipad pro with usb c port, that portable screen with usb c, and a few more things around the camper. It's so nice to be able to use a single cable to connect any of these devices to the other. For example, I've connected the ereader to my phone so I could transfer ebooks directly from the phone to the ereader without having to depend on a computer (It's not a kindle) for example. I also have a usb c hub for the ipad which gives me access to SD slot, several regular usb ports, hdmi out, and more. And all of these devices can be charged fast via PD usb c ports which simply mean that the port have the power delivery standard built into it.
Sorry, ended up rambling a bit. Hope the info helps clear thing up some?