Editing symbols?

[Foxbat]

Just wondering if anybody can help me figure out these:

A black vertical line on the left hand side of the page (there are a lot of them). Any idea what that means?

A red horizontal line? By comparing to my original, I think this might mean indent.


Can't get any idea of the vertical black line through comparing them so thanks in advance to anybody who can help

 

[HareBrain]

The black vertical line is merely to indicate the presence of other editing marks or changes in the text itself. It just says "look at this bit".

 

[Foxbat]

Ha!!! Now that you've told me, I see it!

Thanks muchly