The process of removing insoluble solids from a liquid by using filter paper is known as filtration.
Liquids (such as water, salt solution, oil, and so on) can pass through the tiny pores of filter paper, while solid particles (such as chalk or sand particles) are too large to pass through.
The substance that remains on the filter paper is referred to as residue.
Filtrate is the liquid that passes through the filter paper.
For example - pass a mixture of chalk particles and water through a filter paper, chalk particles do not pass through the filter paper and settle down as residue while water will be pass-through the filter paper as filtrate.