remove array values php

//Delete array items with unset(no re-index) or array_splice(re-index)
$colors = array("red","blue","green");                             
unset($colors[1]);//remove second element, do not re-index array

$colors = array("red","blue","green");
array_splice($colors, 1, 1); //remove second element, re-index array

$unique = array_unique($array, $sorttype)

array_splice(array, start, length, array)