Block jumping

Block jumping is similar to pillaring which is an easy way of travelling upwards. You can easily reach very high places by jumping and placing a block underneath you whilst being in the air.

Blockjumping is basically pillaring on multiplayer in areas the player cannot build in. On most servers there are protected areas in which the player cannot build or destroy. However, you can still reach high places in these areas by placing a block under you and quickly jumping off it again before it disappears. This can be repeated as long as the ping is high enough. A better way of blockjumping that even works on servers with a very low ping is to jump next to a wall and place a block on the wall. Using that way, the block you are going to place is not contingent on the previously placed block.

Most servers run anti-cheat plugins. Most of these will detect blockjumping as flying and kick you from the server or report you to an admin. It is also not allowed on most servers and called an exploit.