There are a wide range of scooter forks on the market today; these are generally broken down in to two main sub categories which are threaded and threadless.
The threaded forks are generally the cheapest available and will generally be found on the majority of the beginner and recreational scooters on the market. Typically these are most commonly found in stock colours which are black or silver.
The threadless forks range in price, style and are generally available in a choice of colours. When running threadless forks on your setup it is important to use a threadless headset and some kind of compression system, some forks come with a compression kit included such as the IHC forks.