Bubble wrap is a packing material that is made from thin plastic with bubbles of air through it. Bubble wrap bubbles come in lots of different sizes, for protecting large or small items in the mail.
A calculator is a small device that does math for you. Calculators have built-in functions from simple addition and subtraction right through to complex angle manipulation functions.
A desk is a kind of table that is used for working on. A desk normally has drawers to keep things like pens and pencils in. Most desks are made out of wood or metal. Desks are almost always rectangular in shape.
An envelope is a special paper container that you put letters into to send them to other people. It costs money to send a letter. You have to buy a stamp to put on it to send it.
A file is a collection of related pieces of paperwork. Files are usually stored inside a file cabinet. The process of storing files is called filing, for example "please file this under T".
On a computer, a file is a block of data that is accessed by its file name.
A file cabinet, or filing cabinet, is a piece of furniture with large drawers in it that have a rail inside. You can hook files onto the rails and store your paperwork inside them.
A keyboard is usually found attached to a computer as a way to type words, numbers and commands with your fingers. Keyboards are also found on typewriters.
