Slider (parachuting)

A slider is a small rectangular piece of fabric with a grommet near each corner used to control the deployment of a "ram-air" parachute. A ram-air parachute has a tendency to open very rapidly. At high velocities, the opening shock from such a rapid deployment can cause damage to the canopy or injury to the jumper. The slider was developed as a way of mitigating this. During deployment, the slider slides down from the canopy to just above the risers. It is slowed by air resistance as it descends and reduces the rate at which the lines can spread and therefore the speed at which the canopy can open and inflate. This invention solved the rapid deployment problem with ram-air designs. Sliders also reduce the chance of the lines twisting to cause a malfunction.

In BASE jumping, when a rapid canopy deployment is desirable, the slider may be constructed of mesh, packed so that the slider is at the base of the lines and does not inhibit the opening ("slider down") instead of up by the canopy, or removed completely. Slider down and slider off both allow the canopy to open with no resistance and are identical in performance.

Slider

In baseball, a slider is a breaking ball pitch that tails laterally and down through the batter's hitting zone; it is thrown with speed less than a fastball but greater than the pitcher's curveball.

The break on the pitch is shorter than that of the curveball, and the release technique is 'between' those of a curveball and a fastball. The slider is similar to the cutter, a fastball pitch, but is more of a breaking ball than the cutter. The slider is also known as a yakker or a snapper.

Slider continuum

Depending on velocity, a pitch can fall anywhere on the continuum from "fastball" to "slider":

The most notable difference between a slider and curveball is that the curveball delivery includes a downward yank on the ball as it is released in addition to the lateral spin applied by the slider grip. The slider is released off the index finger, while the curveball is released off the middle finger. If the pitcher is snapping his wrist as he throws, and the movement is more downward than sideways, then he is probably throwing a curveball or slurve, and not a true "slider". When throwing a slider, the pitcher should create a "dot" on the baseball; this means that as the ball approaches home plate, the rotation of the ball is forming a dot. On a good slider, the "dot" will be down where it is not noticeable for a hitter to pick up. From the batter's perspective, this dot appears white, whereas the dot is red for a curve ball (created by the seam movement), allowing many skilled batters to immediately recognize the type of pitch. By having the dot on the bottom part of the ball, the pitcher will create good depth to the pitch. A good, hard slider has a slight break across the plate and a slight drop on its plane to the hitter.

Slider (computing)

A slider or track bar is a graphical control element with which a user may set a value by moving an indicator, usually in a horizontal fashion. In some cases user may also click on a point on the slider to change the setting. It is different from a scrollbar in that it is not continuous but used to adjust a value without changing the format of the display or the other information on the screen.

Usage with progress bars

Sliders are also combined with progress bars in the playback of streaming media over a network connection (e.g., YouTube videos) in order to show the content buffering position versus the playback position. This is done by superimposing a colored shaded area (progress bar) on top of the slider, indicating whether the user can "jump" forward or not.

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Slider (cricket)

In cricket, a slider is a type of delivery bowled by a wrist spin bowler. Whereas a topspinner is released with the thumb facing the batsman, a slider is bowled in a similar manner to a legbreak, but instead of imparting sidespin with the third finger, the bowler allows his fingers to roll down the back of the ball, providing a mixture of sidespin and backspin. Whereas a topspinner tends to dip more quickly and bounce higher than a normal delivery, a slider does the opposite: it carries to a fuller length and bounces less than the batsman might expect. The sliders will typically head towards the batsman with a scrambled seam (with the ball not spinning in the direction of the seam, so the seam direction is not constant, unlike in conventional spin bowling). This has less effect on the flight and bounce but absence of leg spin may deceive the batsman. Frequently the slider is bowled with a mixture of side spin and backspin. This has the effect of making the ball harder to differentiate from the leg break for the batsmen without reducing the mechanical effects caused by the backspin. This delivery may skid straight on or it may turn a small amount.