A Professional Locksmith has many years of training in how security hardware works, and choosing the proper grade or type of hardware to use in a given situation. Many are certified and / or licensed to practice locksmithing, either by professional associations or by the government where they are in business.
For example, some security hardware, such as a padlock can be very simple as to how it is made or functions, if all you need is a simple padlock, buying it from a