The customer journey is a series of interactions between customers and brands. It's everything from when they first become aware, to when they make a purchase decision and what happens after. It is a very good tool to understand this relationship.
It's very good for identifying touch and pain points throughout the journey. It allows you to put in place the right initiatives at the right time, and in doing so, you can increase customer satisfaction and other results after that.
Most people have the same basic assumptions of customer behavior, which means that many pieces are recognizable. For example, you have a piece about action, a piece about attitude, awareness and relationship. These are all common steps in the customer journey.
I tend to think of two different models. The first is the 5 A's, which is a classic. This model is about the A's; aware, appeal, ask, act and advocate. Which then covers the whole journey. The second model is the Mckinsey loop, which is also a very good tool.