India, Feb. 26 -- Red, brown, purple and many shades of green: Rajesh's vegetable cart is full of colours. The red is, of course, the red of the tomato. But there is another red present, sighted not on the veggie cart, but beside it. This is the red of the letterbox.

Letterboxes used to be intimately linked to the daily life of an earlier generation, in an era where people used pen and paper to write what we today say in emails and WhatsApps. The handwritten pieces of paper would be folded and inserted inside an envelope, the address jotted down on the envelope, and a stamp pasted towards the lifafa's top right (its sticky back often licked wet with the tongue). Then, the letter author would walk to the nearest letterbox and drop the env...