For this application, we are going to use mLab (https://mlab.com/) to host our database as a service. But if you would like to install MongoDB for your local development, you can do so from here: https://docs.mongodb.com/manual/installation/. Once MongoDB is successfully installed, you can run the following command to verify the installation:
$ mongo --versionMongoDB shell version v3.4.10git version: 078f28920cb24de0dd479b5ea6c66c644f6326e9OpenSSL version: OpenSSL 1.0.2m 2 Nov 2017allocator: systemmodules: nonebuild environment: distarch: x86_64 target_arch: x86_64
We are going to use MongoDB 3.4 for our application.