Waste products

Chaff is the husks and stalks that are leftover when freshly harvested grain is threshed. Chaff can be used as a fuel or animal bedding.

Crumbs are small pieces of food. They usually break off from something crumbly, like bread or cake.

Driftwood is wood, usually branches from trees, that has fallen into the water and then drifted around for a while before washing up on a beach that may be a long way from where it fell into the water. Driftwood is often polished smooth by the waves and water, and bleached to a dull grey.

Dust is very fine dirt and lint that drifts through the air and settles on surfaces in your house, making them dull and grey. Dust needs to be cleaned up regularly with a soft cloth. The picture is of some cables from the inside of a computer. They are very dusty.
When there is a storm that picks up a lot of dirt in the air, it is called a dust storm.

Garbage is things that you don't need that have been thrown away. Another word for garbage is trash or rubbish.

Junk is anything that is considered worthless or with a very low value.
What some people consider junk other people may not.

Litter is trash or rubbish that has been dropped on the ground.

Pollution is something that is introduced into an environment that has a bad effect on that environment. Pollution can be industrial wastes, smoke, fumes, car exhaust, rubbish, excess light or heat.

The rind of a fruit is the hard outer layer that you can't eat. Fruits like watermelon and oranges have rinds.

Rubble is broken parts of a building, either leftovers from making the building or as a result of the building being knocked down. ruins are typically surrounded by rubble.