Netflix announced Tuesday that it will end its DVDs-by-mail business on Sept. 29. After that, no more discs will be shipped in the once-ubiquitous red envelopes.

My first reaction was: They still do this?

My second was to recall how cool and convenient it once seemed to be able to order DVD rentals online and have them shipped straight to the house.

Today, in the era of streaming video and pay-per-view, Netflix’s DVD shipments seem almost quaint.

“Those iconic red envelopes changed the way people watched shows and movies at home — and they paved the way for the shift to streaming,” Netflix CEO Ted Sarandos said in a statement.

“We feel so privileged to have been able to share movie nights with our DVD members for so long, so proud of what our employees achieved and excited to continue pleasing entertainment fans for many more decades to come.”

Times change. And few things illustrate that as profoundly as the way technological advances keep reinventing businesses (hi, Amazon!).

Separately, Netflix said it added 1.75 million subscribers worldwide in the first quarter, although the gains in North America were largely flat.

The company also said it will begin cracking down on password sharing in the United States in coming weeks, charging a fee for shared accounts or closing accounts that refuse to play ball.

This past quarter was the first for which we can gauge the impact of Netflix’s cheaper ad-supported tier. It clearly didn’t chase away subscribers.

If anything, the ad-supported tier was perhaps the main driver of subscriber growth, which won’t go unnoticed by other streaming services.

Expect every top streamer to introduce or expand upon ad-supported offerings amid a scramble for subscribers during a period of economic uncertainty.

I’ve been experimenting with some of them. My take: Making people pay a monthly fee to watch commercials feels like double dipping on the part of streamers.

Ads also diminish the viewing experience. I’d advise picking one or two services you really like and going ad-free with them.

Sample the rest via their ad-supported tiers.

Oh, and don’t forget to send in your Netflix DVDs. Late fees can bite.