Cricket is one of the most-followed sports in the world. Millions of people tune in to watch international matches, ICC tournaments and T20 leagues across the globe. One of the core things about cricket is the basic rule-set of the game.Irrespective of the format, some things in cricket remain the same. For example, if a batter hits the ball into the air, and the ball lands directly in the fielder's hands without touching the ground, the batter is considered out in all three formats of the game.The umpire's signals are almost the same in every format. The umpire is neutral and makes fair decisions in a match.Some of the most popular umpire signals are raising the finger to declare a batter out, raising both hands in the air for a six, spreading both hands for a wide, pointing at his knee for a leg-bye, raising one hand for a no-ball, spinning a finger above the head for a free-hit and waving one hand back and forth in front of chest/waist for a four.Even casual fans of cricket would have an idea about the aforementioned umpire signals. But in the modern era, the organizers have introduced some new umpire signals that not all fans would be familiar with.One such umpire signal is the Impact Player signal. You can see the image of that umpire signal here:Johns.@CricCrazyJohnsThe sign from the umpire for Impact player rule in IPL. ( : The Indian Express)8533374The sign from the umpire for Impact player rule in IPL. (📷 : The Indian Express) https://t.co/mshQIsdsplApart from the Impact Player signal, here's a list of three other signs used by umpires that are not so well known.#1 One run shortTo complete a run in cricket, the two batters in the middle need to cross the crease at their opposite ends on the pitch. If a batter just lands his bat on the crease or even falls centimeters short of crossing the line, the run is not considered.David Griffin Photography@dgriffinpixYou don't see many of these...umpire Nick Cook signals 'one short' during the @NorthantsCCC innings against @DerbyshireCCC this evening at Northampton...13You don't see many of these...umpire Nick Cook signals 'one short' during the @NorthantsCCC innings against @DerbyshireCCC this evening at Northampton... https://t.co/iSvQXOR5XsSometimes, the batters are in a hurry as they aim to run two or three runs off the ball. In that situation, they end up running a short run. The on-field umpires keep a close eye on short runs, and if the batter is one run short, the umpire touches one shoulder with the hand of the same arm.#2 Last hour signA Test match lasts for five days in international cricket. The two teams play a fixed number of hours each day. As per the rules, the bowling team needs to bowl a minimum of 15 overs in the last hour.Akbar Kazi@akbarkazi_@Fenda_India @Contest_in @contestmantra @Contest_AlertAns2) Umpire Signal for last hour of Play #CheakyourCriclQ http://t.co/qcNEqbwv5y@Fenda_India @Contest_in @contestmantra @Contest_AlertAns2) Umpire Signal for last hour of Play #CheakyourCriclQ http://t.co/qcNEqbwv5ySo when the final hour of any day begins, the umpire points towards his wrist watch, reminding the fielding team that the final hour is about to start.#3 Penalty runs signalLike other team sports, there is a rule for penalty in cricket as well. Whenever a team or a player breaches the rules, the on-field umpire can penalize them. For example, if the ball hits the wicket-keeper's helmet lying on the ground, the fielding team is penalized five runs.Cricket Mentor@Cricket_MentorON THIS DAY IN HISTORY - 20/8/2006: We witnessed the first ever forfeited Test Match, when Pakistan refused to return to play after Umpire Darrell Hair docked them 5 Penalty Runs for ball tampering…🤔🏏 This lead to England being awarded the match… #Cricket1ON THIS DAY IN HISTORY - 20/8/2006: We witnessed the first ever forfeited Test Match, when Pakistan refused to return to play after Umpire Darrell Hair docked them 5 Penalty Runs for ball tampering…🤔🏏 This lead to England being awarded the match… #Cricket https://t.co/D7SUBTZCBBIn that situation, the umpire places one arm on the opposite shoulder to signal penalty runs. It is rare to see penalty runs in a match.