Each of the following online slot game types offer a distinct but different gameplay experience. The types of slot games we will be looking at include progressive jackpot slots, slots with high return to player percentages and aesthetic branded slot games which are popular but offer fewer potential wins for players. This includes how randomness and probability occurs. This article will aim to introduce the science used in different types of slot games. Online casino gaming in the UK remains immensely popular. In 2020, online searches on Google in the UK for casino related keyword terms reached an all time high. Due to the technological advancements since the turn of the millennium, the majority of casino games are now played online via slot sites. According to the latest studies, slot machines are the most popular type of casino games played in the United Kingdom.