In Lotus Notes, you can use two types of Notes/FX fields.
One-way fields
One-way fields provide information for exchange in only one direction, from the embedded object to the Notes document. For example, to exchange the data in the Microsoft Word document file property Created, with a field in a Notes form, you first have to create the field in the Notes form and name it "DateCreated."
When you complete the setup for Notes/FX field exchange, changes made to the Word document property Created appear in the DateCreated field in the Notes document; however, changes made in the DateCreated field in the Notes document do not affect the Word document file property Created.
Two-way fields
Two-way fields provide information for exchange in two directions, from the embedded object to the Notes document and from the Notes document to the embedded object. Two-way fields are updated in the embedded object when you open or activate the embedded object and in the Notes document when you close the embedded object and return to the Notes document. For example, to exchange the data in the embedded Word document file property Title, with a field in a Notes form, you first have to create the field in the Notes form and name it "Title."
Changes made to the embedded Word document file property Title appear in the Title field in the Notes document, and changes made in the Title field in the Notes document appear in the embedded Word document file property Title. Custom document file properties are also two-way fields when you set them up for field exchange in a Notes form.