On chargers and phones

Why this post? The number of "Will this charger work with my phone?" or "Will I damage my battery using this charger?" posts that you see in public fora such as Reddit is quite disturbing. It shows a global lack of understanding of the basic fundamentals that everyone should know to prolong the life of their devices and of themselves in some cases. I'm hoping to address some of the misconceptions out there in the wild. Charging Protocols Brief history Back in the "old" days there were no charging protocols, or at least there was nothing standard. Each manufacturer would do its own thing with different charging connectors and different chargers providing different voltages. Even different products from the same manufacturer would have different charging requirements leading to people having drawers full of different chargers. Then came USB. The USB 2.0 (introduced in 2000) type A outlet on laptop and desktop computers was a conve...