'webpack-dev-server' is not recognized as an internal or external command, operable program or batch file. npm ERR! code 1 code example

Example 1: 'webpack-dev-server' is not recognized as an internal or external command

npm install webpack-dev-server --save-dev

Example 2: 'webpack-dev-server' is not recognized as an internal or external command

npm install -g webpack-dev-server