Categories can also be used to attach metadata to an information object (reference, note, task, chart). Metadata is data about other data. For example, if you have a note in the notes module about a laptop computer, you can have other data about the content of this note. When talking about laptop computers, people usually want to know its processor speed, memory, graphics, etc. You can have a list of such attributes about the computer that is not mentioned in your note. These property-value pairs can be linked to your note to form the metadata for that note.
To assign metadata to an information object, the first step is to create a list of categories that will be used as the properties in the property-value pairs. Open a categories folder, use the category Quick Add box to enter "Processor", "Memory", etc. and press the Enter key after each word to add it as a new category item.
Open the note about laptop computers and click the menu command "Note | Add Links | Link to Category...". On the left panel, select the categories folder that contains the categories you want to link to. In the middle panel, select the categories you have added. These categories will become the property part of the property-value pair. On the right panel, select the "Cross Links" tab. Under "Link relationship", select "Metadata". If you don't want to add backward links, check off the box "Add reverse link". The reverse link relationship will change according to the selection of the link relationship. Leave the "Description" box blank. Now click the "Add Links" button. Once the links are added, click each cell under the Description column and enter the value part of the metadata property-value pair.
Click the "Close" button to go back to the note window. Select the "Links" on the right. You can see all the added metadata pairs. If you need to edit any metadata value, you can click on the cell under the "Description" column to edit.
