Balsamiq was the very first tool that helped me learn about wireframes and it is also the tool that I have used to make most of my raw wireframes. The best part of it is that it provides very easy to understand pull down icons and options from the top bar which makes the wireframing journey smooth and easy to learn and build the wireframe.

The Balsamiq Mock Ups software has a very easy learning curve and good standard setup. I can easily and quickly create simple wire-frame examples for a proposal, or a much more complex UI design wire frame set. The built-in library of shapes, containers, and icons is helpful in getting common tasks done that are relevant to my web development practice. There is no limit to what I am allowed to make (flow charts, UI designs, admin flows, site maps, etc.) and I can create as many project buckets and pages as I want. Many of the SAAS competiting products have a lot more limitations.

Easy to use tool that will allow you to build a prototype in minutes to share with your team or with customers.