There are various job titles in the wedding planning business, and you may hear some of them in your wedding planning career.
This title and wedding planner are used interchangeably. But there are certain individuals that call themselves wedding coordinators that only coordinates the wedding ceremony and some churches employs these people for this specific purpose.
A wedding planner is involved in the complete planning and organizing of the wedding. They manage the planning process, coordinate all parties involved and they provide consultation.
A wedding consultant has little to do with the planning of the wedding. A wedding consultant is narrowly focussed positions like someone who helps with the selection of a wedding gown, or someone who knows the ins and outs of wedding flowers. These people will likely work in a retail store.
This is the same as a wedding planner, but can also be used to refer to people that work in retail stores that focus on working with brides.