"ipfs add" and "ipfs files write" the difference between the two

[VKingi]

1. When I use commands:

 ipfs add test.mp4

hash value: QmS2sz7WNaVMDbbuBdzLVNVXwtWsNyNs3S4KjFaYY87aAV

2. When I use commands:

cat test.mp4 | ipfs files write --create /test/test.mp4

hash value: QmazXU4S74VbLjqLouNMuJhKnWp5XKnyp7qqLnRmD3WLgu

Obviously the two hash values are different,But when I used "ipfs get $hashValue" to download the files, I found they were identical

My question:

1. Why are they different?
2. Why are there two ways to add files, and the difference between them?

All these problems have been bothering me, but I still haven't found the result. Please help me, thanks.

[Stebalien]

I'd be happy to answer your question on discuss.ipfs.io or on the #ipfs freenode IRC channel (you can flag me down by mentioning "@Stebalien").

[VKingi]

Is it because I'm not good at English that you don't understand me?

[Stebalien]

It's just our policy to keep the noise down on this issue tracker.

🔥❓If you have a QUESTION about IPFS, please ask on our forum at https://discuss.ipfs.io 🔥❓