Bleed (printing)
Bleed in printing is like a safety zone around your design. It's extra space beyond the edge of your artwork that gets trimmed off after printing. This extra space ensures that your design goes all the way to the edge of the paper without leaving any white borders. So, when you design something with bleed, you're making sure that even if the cutting isn't perfect, there won't be any blank areas around your design. It's like giving your artwork a little extra breathing room to ensure it looks its best when it's printed and trimmed.
We require at least 3mm bleed on all outer edges.
Why is bleed important?
Your design is printed on a bigger sheet of paper and then cut it down to size, matching the size and shape of your artwork template. Sometimes the paper can shift when it's cut, without bleed this would leave white areas on the edges of your artwork.
Read more about bleed on Wikipedia: