This paper aims to introduce readers to the Lean philosophy and has therefore been written with non-expert reader in mind. After this historical introduction, the paper will continue to explain the concepts of value and waste. This will be followed by a detailed description of the stages required for the implementation of a Lean methodology and an explanation of the tools necessary to keep it in place. The paper ends with a description of the five basic principles of the Lean philosophy together with an overview of other concepts supporting that support it.