"Integration" and "infusion" are terms that are used interchangeably, especially in an educational context. However, they actually have two different meanings. Infusion is when a new element is introduced into something. Integration, however, refers to when two different elements are mixed together that were segregated before. When teachers use the word in an educational context, they are typically referring the process of making technology available to the students and the teachers.
Integration and infusion both involve two separate elements that are joined into a unified whole. However, the ways in which the two distinct elements become a single object varies between the two concepts. Integration specifically is the concept of using technology seamlessly in the classroom. Teachers must use the technology in the right context as a learning facilitator. Infusion does not necessarily imply that the teacher chooses the context in which the technology is used.
Things that are integrated could be mixed without actually being physically joined together. For example, different groups that are integrated will likely interact with each other, but won't actually be joined. The term "infusion" is not often used to describe groups coming together. Infusion implies more of an unplanned and random injection of one thing into another. With integration, the two or more different objects are mixed together in a pattern that is often planned.
Integration implies that the two things being integrated are equal in importance. When technology and traditional curriculum are integrated, they both are treated as equally important and are integrated because they will be improved if they come together. However, infusion is often considered a smaller thing that is injected into a larger thing. Therefore, when technology is infused into classrooms, it becomes an element that is subordinate to the goals of the traditional classroom, only being used to improve the quality of that into which it is infused. Infusion is the act of introducing one thing and not introducing both parts simultaneously.