View the full OSF FAQ
Component - A sub-project to help you organize different parts of your research. Components have their own privacy and sharing settings as well as their own unique, persistent identifiers for citation, and their own wiki and add-ons.
Folder - Folders are used to organize files within a project or component
OSF Registration -- A registration is a frozen version of your project that can never be edited or deleted, but you can issue a withdrawal of it later, leaving behind basic metadata. The project can continue to be edited and updated, providing you the option to register your project at different points throughout the research cycle.
When you create the registration, you have the option of either making it public immediately or making it private for up to four years through an embargo. A registration is useful for certifying what you did in a project in advance of data analysis, or for confirming the exact state of the project at important points of the lifecycle, such as manuscript submission or the onset of data collection. Read more about registrations here.
Forking - Forking a project creates a copy of an existing project and its components. The fork always points back to the original project, forming a network of citations. You might a fork a project to expand upon another's work. For example, a professor may create an OSF project with student assignments. Each student forks the project to have his or her own copy of the materials to start his/her own work. More information about forking can be found here.
View-only links - View-only link offers a way for you to share the private contents with non-contributors. You can create an anonymized view-only link to hide your contributor names in the project - this is particularly useful in blinded peer review! More information on how to create a view-only link can be found here.