Question about Child Layers

[Jaffa]

I have been creating many standard layers and child layers -  it seems forever.  However, one thing I have taken for granted up to now is that I am creating Child Layers in the correct way.

However, have just realised that Windows Affinity Photo shows a small perpendicular line and that seems to be the normal way to achieve it.  The way I have been doing it is to drop the

adjustment layer into the blue line that does not extend all the way to the left, my image re-inforces what I mean.

My overall question therefore is - what is the difference between using the "partial" blue horizontal line and the small blue vertical line?  (Note: I fully realise that the "full" blue horizontal line is

used to create a parent or standard layer).

[Alfred]

When you drop a layer just below a shape layer to give you that partial horizontal blue line, the dropped layer is clipped to the shape so that the parts outside of the clipping shape disappear, but the clipping shape remains visible. When you drop the shape onto the thumbnail of the other layer, you get that small vertical blue line and the target layer is masked by (or cropped to) the shape that you dropped on it, and the masking/cropping shape disappears.

[R C-R]

Watching the Affinity Photo - Clipping vs Masking video tutorial may make this clearer. (It works the same in all Affinity apps.)

[Jaffa]

Many thanks for your responses, RC-R and Alfred.  I have watched the video tutorial a couple of times and now understand.  What confused me at first, was that I wondered how I had managed fine, so far.  However James Ritson, explains that at the end when he says that both the clipping and masking work the same when you are dealing with adjustment layers, etc.  It is just in situations I don't really encounter at this stage, that the difference is crucial.