To lay a proper foundation for your product, you need to understand your users and build great UI --- and particularly your first users. In turn, to know your users, you want to do three things:

• Identify a problem that they actually need to be solved,
• Understand their pain points, and
• Step into the shoes of your users, to determine their wants and needs, by creating “user personas.”  

What are "User Personas"?

User personas are fictional characters you create to anticipate the different users who will use your product.  The process is designed to help you deeply understand your customers’ needs.  As shown below, “user personas” can be very detailed, and they’re not just about objective facts.  They also help you understand your customers’ values, fears, goals, and challenges:

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