SAMR is a model designed to help educators infuse technology into teaching and learning. Popularized by Dr. Ruben Puentedura, the model supports and enables teachers to design, develop, and infuse digital learning experiences that utilize technology. Source: Kathy Shrock's Guide to Everything
The is a lot of controversy about the SAMR model. Mostly, because technology use cannot be categorized quite this cleanly. This model seems to denote that there is only one way to go with technology - in a linear fashion.
This image speaks a bit more clearly to the average person: