Unit operation

A "unit operation" is like a toy box with lots of different toys. Each toy does a different thing like a car goes vroom vroom, a block stacks up high, or a ball bounces. Think of the toy box as a giant machine that makes something. Each toy is like a step in making the thing.

For example, if you wanted to make lemonade, you would need to squeeze lemons, mix in water, and add sugar. Those are each like a "unit operation" - each step is important to make the lemonade taste good. In bigger machines, there might be hundreds or even thousands of "unit operations" to make a product like a car or a computer.

So, a "unit operation" is just one step in making something, and each step is important to make the final product just right.