It has also been recognised that ties and networks can be intentionally built, created and maintained as resources for learning and working (Burt,
Technologies included in PLNs offer basic to advanced functionalities (such as search, access to content, user–made content classification, personal knowledge creation and presentation and communication with peers and others), which learners can employ, change and adapt to suit their learning needs (Attwell, et al., 2009). These tools allow learners to structure and manage the complex environment of people and content around themselves according to their own personal preferences.