Explanation of the three types of sign up buttons on projects; joining a project with dates, expressing interest in an anytime project, and applying for a project with approval restrictions.
Joining a project means you are signing up for a specific time slot on a specific date with a role associated with that time slot. This is the most common type of project in VOMO. These projects do not have any approval restrictions (i.e. "organizer approval" or "background check required").
Expressing interest is found on Anytime projects. These projects do not have any dates, time slots, or roles. It is simply a way for the organization to gather interest from potential volunteers signing up for the Anytime project.
Applying for a projects will appear when a project with dates, times and roles also has approval settings activated (i.e. "organizer approval" or "background check required"). Because you need approval from the organizer you are applying for the volunteer role you chose. When you apply, you will be in a pending state until the organizer of this project either approves or denies you for the role and time you chose.