Embed or just link?
Embed is untidy and link is tidy
If we imagine our file like a box that contains images. Embed means we will take the image that we want to put in the box make a copy and include that in the box. If we link this means that we do not put a picture in the box but we just draw in the box saying "picture1 goes here". Visually Inkscape showes the same thing: you will see your image in your canvas. But the first option[embed] makes your file bigger (and maybe eventually slower?) the latter option [link] means that if you have to move your work area you have to move all the files. But when you publish your image to a *.png you get the same result with both.