The Finder’s column view is a very useful way to navigate through your folders and help you find the document you’re looking for quickly. You can switch to it from either the icon or list views by using the Option-3 keyboard shortcut.
However, there is one downside: if you have long file names, the columns never seem to have enough width by default to read it all. You can, of course, resize them by dragging the separator between two columns: they have a little handle at the bottom for that very purpose.
If you want to alter the default column size, Alt-drag that handle. This will not only increase the size of all columns in every open Finder window, but that new dimension will now become the default whenever you open a new window.
If you’d rather resize a single column, instead of dragging that handle, double-click on it: this will increase its size just enough to not truncate any name contained within.