Cables - slip knitwise or purlwise?

I am just starting on cables, and I’m not sure if I should slip stitches onto the third needle knitwise or purlwise? I’ve seen how-to videos that demonstrate both, so I guess they both work. But what would be the difference in the end result?

thank you!

It’s odd they would show both, unless some are meant to be twisted which happens to a st when slipped knitwise unless you’re going to use it in a decrease. Stitches put on a cable needle should be moved purlwise - it’s the same as putting the cable needle point to point with the left needle and just sliding them along.