The padlock is a portable lock that consist of a solid body, a locking mechanism and shackle with various and different styles. Most padlocks used solid metal bodies with the exception of disc padlocks and some combination padlocks which are the strongest part of the padlock. As the size of the padlock increases, then the larger the key way and locking mechanism it can be. The key way and locking mechanism usually contains between three (3) and seven (7) small pins which are spring loaded so that the shackle will pop out when unlocked while other padlocks have to be manually removed. The shackle or shank is the U-shaped bar that loops round from and back into the padlock body. It is the most exposed part of the padlock and more susceptible to be attacked. There are many types of padlocks that was designed differently with a different properties.
Reference:
https://en.wikipedia.org/wiki/Padlock
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