When installing a deck there are two common options on fastening the decking boards down.
Screwing - using 8G, 10G and 14G screw depending on the size of the decking board, generally in stainless steel these are the most preferred option for a few reasons.
They are made made from stainless steel so are a great option outside and close to the coastline, they are visually pleasing having all of the screws line up. With their thread and large head they are the most effective of the two options in holding down a decking board.
Nailing - using stainless steel twist nails is another option commonly used. Having an attractive small stainless head these are more subtle. However over time they will allow the board to pop as the twist shank is not as strong as the thread on a screw. Combined with the smaller head.
There are other alternate ways to fix off a deck which involved hidden fixing systems which are not your traditional methods which also have pros and cons aswell.
In our opinion we prefer using stainless screws as they look smart and are great from a maintenance point of view should you need to access under your deck or need to replace a board.