Perforation Explained

The term perforation is used to describe a series of holes applied to paper enabling a section to  be easily torn off without damaging the rest of the sheet.
Adding perforations (commonly referred to as perf lines) avoids the user having use  scissors and adds to the convenience, e.g, a voucher book can be carried in a wallet and used in a shop one voucher at a time.
Perforations are applied either using a perfing wheel or a die cutting process which stamps the perforated lines into the paper.
The method used will largely depend on the number of perfs being added and the quantity of the run.
Although the primary use of perforations is to create a tear off section, they can also be used to replace the scoring process, allowing thicker materials or multi folded sheets to lie flatter.

Standard perfing vs microperfing

The holes which have been cut into the paper will cause a serrated edge to be left behind once the tear off section has been removed.
This is fine for most items, e.g tickets, vouchers etc but sometime a neater edge will be desirable.
In this instance microperfing is the answer.
As its name suggests microperfing uses much smaller holes to create a perforation which is just as strong but leaves behind a neater torn off line.