Register application to get API Key and Shared Secret

Go to http://www.flickr.com/services/api/keys/ and click on 'Apply for a new key online now'

Fill in the form and click Apply. Flickr will give you a new key that looks something like:

   0123456789abcdef0123456789abcdef

which is the API Key

Then authenticate it to get the Shared Secret which looks something like:

   fedcba9876543210

You need to choose the authentication type. Here the type 'mobile' is recommended since no callback URL is usually appropriate for a command-line application or library. Set the permissions to 'read', 'write' or 'delete' as appropriate.

The result will be a new key with an 'Auth mode Mobile' and an authentication URL that looks like:

   Mobile (http://www.flickr.com/auth-11111111111111111 Read)