Gallery blocks have two settings: the number of columns, and whether or not images should be cropped. The default number of columns is three, and the maximum number of columns is eight. This is my edit of this post.
Boat BW PB Barco Texture Beautiful Fishing
Some more text for taking up space.
A two column gallery, aligned to the left, linked to media file.
In the editor, the image captions can be edited directly by clicking on the text.
If the number of images cannot be divided into the number of columns you have selected, the default is to have the last image(s) automatically stretch to the width of your gallery.
A five column gallery with normal images:
