Nodes are containers for ideas about your data and can be seen as representing the themes or categories that emerge from your Sources. We liken nodes to files held within a suspension filing cabinet – as a theme emerges from our data, we take that ‘chunk’ or ‘scoop’ of material/s and place it in one of our ‘files’ that has been appropriately named for the theme we are coding. Later, these nodes can be used to ask questions of our data, and importantly, we can also store the results of the questions we have asked, i.e. the interrogations of the data we have completed, as nodes.

Your project can have as many nodes as necessary (watch, however, that your overall number of nodes is not too large) and can be organised into a hierarchy or, if you prefer, need not be organised at all. As nodes are highly flexible you can create nodes at any time and you can alter the way you have organised them as you rethink your ideas. Depending upon your methodology, you may choose to create your nodes at the beginning of your project and place your coding into nodes later, or you may elect to create them as you perform the coding itself (or indeed, a combination of the two!). All nodes have names and addresses, and may optionally have coding and descriptions.

Nodes represent more than just themes though - NVivo 8 has five different types of nodes which are described below:

Free Nodes: These are a 'stand-alone' node that has no clear logical connection with other nodes and does not easily fit into a hierarchical structure. (A Free Node can also be a ‘node-in-waiting’ that resides in the Free Node file until you see fit to relocate it.)

Tree Nodes: Nodes that are organised in a hierarchical structure moving from a general category at the top (the parent node) to more specific categories (child nodes) or even into categories that are more specific (grand-child nodes).

Case Nodes: A node with attributes such as gender or age. You can use cases to gather content about a person, site, institution or other entity involved in your research.  Like tree nodes, case nodes can also be organised in hierarchies.

Relationships: A node that defines the connection between two project items. For example, the relationship between two cases (Anne loves Bill) or between two nodes (Poverty impacts Health).

Matrices: A collection of nodes resulting from a Matrix Coding Query.