Explain digital cameras?

Disruptive technologies, too, can be subtly disruptive, rather than prominently so. Examples include digital photography (the sharp decline in consumer demand for common 35mm print film has had a deleterious effect on free-riders such as slide and infrared film stocks, which are now more expensive to produce) and IP/Internet telephony, where the replacement technology does not, and sometimes cannot practically replace all of the non-obvious attributes of the older system (sustained operation through municipal power outages, national security priority access, the higher degree of obviousness that the service may be life-safety critical or deserving of higher restoration priority in catastrophes, etc).