Downloading a song and playing a song are two different actions.

Are they really? If you are playing a song in your web browser, how did it get on your computer? Hint: your web browser downloaded it for you.

When you play in the browser, you are playing on youtube. when you download, you can play wherever you want. This is similar to saying I'll go record a movie from a cinema hall and watch it later at home since I paid for it.

No it's just a simple, direct assessment of a situation. There is no technical difference between "streaming" or "downloading" the bytes. In each case, the exact same thing happens, the numbers are copied to the local machine. The distinctions are a legal fiction that doesn't actually have a reflection in the real reality, and as most imposed fictions end up, there is very little respect for the idea on the ground.

True, but at the end of streaming, the provider/browser clears the cache. The legality of it is debatable, but downloading copyright material is certainly not legal. If someone visits me at home and uses my coffee-maker the action is same as taking it to his home and using, but only one of them is acceptable.

Which one is acceptable? Someone breaking into your home to use your coffee maker or someone asking to borrow it for the weekend?

I did not say breaking in. That would be equivalent to hacking. If i'm home and I let my friend use my coffee-maker, that is analogous to youtube giving you a license to watch a video.

I apologize for the confusion. I read your original comment to be a comparison between letting someone use your coffee maker (lending) and someone stealing your coffee maker which I believe is how you intended it. My comment was intentionally obtuse and was intended to highlight problems with your metaphor. I do not believe that letting a friend use my coffee maker is analogous to youtube granting me a license to watch a video. For instance, I have no desire to recoup my electricity costs by displaying advertising to my friend while she is making her coffee.

Too bad you don't like monetizing. The metaphor is still valid.

Is the browser obliged to clear the cache?

Yes - see:

Cache-Control

Expires

max-age

See https://developers.google.com/web/fundamentals/performance/o...

But technically if you write your own browser, these are just guidelines and you don’t have to respect them, right?

Alright Einstein! make you'r own bump/skeleton key, break into people's home and take stuff.

I don't think this is the same thing at all. If someone slides an envelope under my door that says "Please do not open" am I obliged to leave it sealed? What if I open it anyway and the contents advise me to destroy the message, am I obliged to do this?

What if you go to a friend's house (youtube) and see a letter that says do not read. But you whip out your camera phone, take a picture, come home and read? The discussion is not about what is possible or should be done, it is about what is legal/moral.

When you watch a video on Youtube, you are essentially given a license to watch that content on their site. They show some ads and make some money. When you download, you are violating that license.

Depends on the jurisdiction. Some make a explicit difference, e.g. German law speaks of (rough translation of the critical bits by myself) "temporary reproductions that are [...] integral and necessary part of a technical way of a) transmitting through a network [...]" which in practice means that streaming is ok in cases where explicit saving is not. For private use, downloading from not clearly non-legal streaming sources is fine though (again, in Germany)

I believe streaming vs downloading has slight implication differences. E.g if they choose to shut it off you can't stream anymore. Or force ads or view counts. Yet in downloaded form you are bypassing those things that have value

How does that work with the "time shifting" laws that allowed VCRs to be used? Isn't this basically the same thing?

One problem is that you're not only time shifting but space shifting to digital media as well. And the laws as written are very specific as to what is permitted.

Example: In the US, the AHRA that makes personal space shifting digital audio legal (relevant to the submission) is fairly limited in the media that can be used for copying. Though I agree that they're being used for basically the same thing, computer hard drives aren't covered.

A relevant quote from Wikipedia [1] that sums up why I think this act falls short of its purpose: "In each case, the principal distinction between what is and is not covered by the AHRA is determined by whether or not the device is marketed or designed (or in the case of media, commonly used by consumers) to make audio recordings, not the device's capabilities."

[1] https://en.wikipedia.org/wiki/Audio_Home_Recording_Act#Digit...

I don't get the distinction. Why is saving a stream to an mp3 space shifting but recording a broadcast to a vhs not?

Time shifting means copying for the purpose of listening to the recording at a better time, whereas space shifting is relevant here because the intended purpose is to allow the audio to be played in a different environment (i.e. not the YouTube player or app).

The more important thing is that space shifting to different media (digital, personal computer hard drive in this case) is legally treated differently. Though, to be honest, I'm not convinced that any personal recording protections would or should apply to the YouTube situation. It's just one way that the two differ.

Not at all similar. They can show you ads if you go to Youtube, it's how they make money. There are no ads when you download it.