I've never been up on this kind of stuff. I am looking to buy a couple of lightening cables for my iPhone 7, but they say the charger has to have a USB-C port. My Mac says it has a usb 3.0. Do I need an adapter?

Yes, I'd say you do:

https://www.amazon.com/usb-c-3-0-adapter/s?k=usb+c+to+usb+3.0+adapter

But it's rather confusing. Seems like there should be two different male/female adapters, depending on if you need to plug a cable in or plug in to a device.

I finally found out that a usb-c is the same as thunderbolt. Since I only have a thunderbolt port on my Mac and nowhere else, I decided to find some lightening cables with usb type A to match all my chargers. Eventually when everything like that phases out, I will get usb-c products including usb-c chargers or the adapters as you've mentioned. Thanks for your response and for the link to the adapters. That is helpful.

If I remember correctly, Thunderbolt 4 is the same as USB C, but Thunderbolt 3, which I believe you've got, is not 100% compatible.

Hmmm. OK. Maybe it's good I decided not to go that route.

For what it is worth, to ensure the future usefulness of my connecting cables, I have slowly been replacing all of my USB and Thunderbolt cables with cables rated for Thunderbolt 4 and so marked on the connector and using appropriate HDMI, Thunderbolt 2, lightning, and Type A adaptors. NOTE: be sure the type A adapters are rated USB 3.1 Gen 2 to ensure best performance.

Thunderbolt 4 is not cheap and gets even pricier once you go over 24 inches in length, below that the cables are passive and longer than that they must have active electronics in the connectors. But I look at this as an investment, and expect to recoup the cost in the long run.

NOTE: be sure the type A adapters are rated USB 3.1 Gen 2 to ensure best performance.

The description on Amazon never mentioned anything about USB 3.1 or Gen 2. It's been ordered so let's hope they work.

If the USB protocol (ie. USB 3.1 gen 2) is not specified it is safe to assume they are USB 3.0 and As far as I know Lightning connectors are USB 3.0. So they will work but they will limit the throughput of the circuit to 5 Gbps. USB 3.1 gen 2 adaptors are capable of 10 Gbps and that can make a noticeable difference when connecting to higher speed devices such as external hard drives.

If the USB protocol (ie. USB 3.1 gen 2) is not specified it is safe to assume they are USB 3.0 and As far as I know Lightning connectors are USB 3.0.

According to the seller on eBay, the lightning cables he is selling had to use USB-C ports. That's why I didn't buy from him.

You, and apparently the seller on eBay, are conflating USB port type and the USB standard. The USB standard (3.0, 3.1, 3.1 GEN 2, 3.2, 4.0) is a function of the number of wires in the and shielding in the cable and port. The USB port type (A, A 2.0, A SuperSpeed, B, B SuperSpeed, C, Mini A¹, Mini B, Mini AB, Micro-A¹, Micro-A super SuperSpeed, Micro-B, Micro-B A SuperSpeed, Micro-AB, Micro-AB SuperSpeed) describes the physical shape of the connector and all of those can be used with more than one protocol and connector type C can be used with every protocol from 2.0 to 4.0 plus Thunderbolt 3 and Thunderbolt 4. The Lightning connector is an Apple proprietary connector for USB 3.0 standard devices.


That is a lot of information to digest and on the theory that a picture is worth a thousand words this Wikipedia article has an excellent chart of the "Available connectors by USB standard" showing the relationship between connector and standards. Every USB standard is [b]backward compatible with all of the previous standards[/b], but the device in the loop with the lowest USB standard sets the maximum data transfer rate.
My reason for emphasizing getting USB 3.1 gen 2 rated adaptors is because that gives you at least the potential for a 10 Gbps cable setup.
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1. Connector types in red are the port types you are most likely to encounter.

Wow, TMI! Let's just hope my cables work with my chargers.