When we learn a language, there are four skills that we need for complete communication. When we learn a language, we learn to listen first, then to speak, then to read, and finally to write. These are called the four "language skills".

The four language skills are related to each other in two ways:

• the direction of communication (in or out)

• the method of communication (spoken or written)

Input is sometimes called "reception" (listening and reading) and output is sometimes called "production" (speaking and writing).

Spoken is also known as "oral".