Create an account or sign in now before publishing your post, if you want to be able to edit it or delete it later.
On one hand, by clicking on 'Giving the full address', you will be able to enter the exact address of this location and pinpoint it on the map below.
After your post has been created, you will be able to visualize it on the home page map with a colored marker placed at the previously marked location.
On the other hand, you may not want to give away that many details about the location, given any personal reasons (eg. anonymity, details about the post...).
By choosing 'Selecting the area only', you will just have to indicate which area does this location belong to. Once the post is created, it won't appear as a colored marker on the home page, but it will show up in the search results page related to the selected area.