The most "personalized" form of learning involves a student diving into what interests he or she the most and doing it at a pace and in a context that makes sense for them. (Sounds like the best graduate program in the world!) For younger students who are still discovering what interests them--and how they learn--personalized learning also mean how education is delivered to them.
The most "personalized" learning experience for anyone would involve a tutor for every learner. Good teachers skillfully adapt what they're teaching to their students' interests and abilities.
When it's not possible to provide a great 1:1 instructor for every learner, technology can play a crucial role.
Many fans of education technology believe that specialized technology is the most effective way to deliver "differentiated" instruction that is "individualized," or "personalized" to a large number of learners, with diverse backgrounds and learning styles. There's a lot packed into that sentence because those terms get used interchangeably. At least according to experts, each of those terms has a subtle difference.
Here are the definitions proposed in the National Education Technology Plan of 2010:
Individualized learning means instruction is paced to the learning needs of different learners. Learning goals are the same for all students, but students can progress through the material at different speeds according to their learning needs. For example, students might take longer to progress through a given topic, skip topics that cover information they already know, or repeat topics they need more help on.
Differentiated learning means instruction is tailored to the learning preferences of different learners. Learning goals are the same for all students, but the method or approach of instruction varies according to the preferences of each student or what research has found works best for students like them.
Personalized learning means instruction is paced to learning needs, tailored to learning preferences, and tailored to the specific interests of different learners. In an environment that is fully personalized, the learning objectives and content as well as the method and pace may all vary (so personalization encompasses differentiation and individualization).
Source: Karen Cator (edSurge: edition 016); National Education Technology report, page 12.
Barbara Bray and Kathleen McClaskey, co-founders of Personalize Learning, LLC created the Personalization vs. Differentiation vs. Individualization (PDI) chart in 2012 and updated it to Version 3 in 2014. This PDI chart is used by millions of educators worldwide and has been translated into many languages. You can download the PDI Chart and other charts including the Stages of Personalized Learning Environments (PLE) Chart on the website on the Toolkit tab. You can also read in more detail about the PDI Chart and Stages of PLE Chart in their recent publication, Make Learning Personal.