A Navajo weaving of an integrated circuit: the 555 timer

The continued popularity of this chip confuses me. I don't understand why it didn't get forgotten decades ago as microcontrollers became common place. Though compared to the Pentium talking on older designs is likely faster to make, so I wonder if he markets himself to an older audience who is nostalgic for these ancient chips.

Because it's fun and there are many readily available DIY designs that use it.

You may be right about nostalgic reasons, but as a freshman during the emergence of microcontrollers, I've asked the same question to and old professor, in the sense of "why discrete digital electronics is still widely used?".

His response still resonates with me today: a military grade 555 would work in extreme conditions (e.g. heat), would last pretty much forever, would consume virtually no power, and will still cost you a penny.

Sometimes that's exactly what you need. Reliability, durability and cost trumps the power of programmability.

Well even if we assume there's a suitable 8-pin microcontroller which doesn't cost more than the 555, merely loading the firmware onto the microcontroller is going to add significant cost and complexity to the manufacturing stage. Also the microcontroller would be far more sensitive to power supply inadequacies because its state consists of much more than a capacitor and a flipflop.

The world would be a much sadder, drearier place without the 555. That's the nostalgia part out of the way.

Really it's such a useful almost universal lego block of a component that it's hard to imagine it going away anytime soon. Sure microcontrollers are as cheap as chips these days, but you get a lot more with them. Do I need to say that sometimes more is less? Can think of scenarios where you absolutely don't want to see a chip containing firmware/code which needs auditing and locking down.

Back in the day you'd go into an electronics store and there'd be books containing just 555 circuit recipes. Not to mention the magazine articles.

And every EE student back when we tied onions to our belts must have had a lab assignment to spec out a PLL using 555 and bits and bobs and then measure transient responses, temperature stability, etc.

The original bipolar variant of NE555 is likely to have a lifetime of many decades, if not more than a hundred years, even when operated continuously in harsh environments.

A modern CMOS microcontroller has a much more limited lifetime. Depending on model, you can hope for 10 years or 20 years, but not much more than that because very small MOS transistors and flash memory cells eventually die, unlike the more robust bipolar ICs (whose active regions are buried in the semiconductor crystal, not located at its surface, like in MOS devices).