A jump map contains a series of difficult trick jumps, often requiring skills and techniques that are rare or impossible to perform in regular play. Generally, the player has an infinite supply of ammo and health, and any failure to meet the requirements of a specific jump will teleport you back to its beginning. A jump map is a map commonly used to test how good the player is at skilled jumping. Most jump maps are for the Soldier or Demoman. However, there are Scout maps and even Engineer maps. Jump maps normally use Jump Mod to keep the players from dying or having to reload while jumping.
Soldier Jump Maps
Soldier jump maps are maps designed for the Soldier class, primarily to use their Rocket Launcher to rocket jump across a room or obstacle with the objective of making it past the final obstacle of the map. Understanding how to properly perform the various methods of rocket jumping and the knowledge of a map's layout is required to navigate through rocket jump maps. The required knowledge of rocket jumping to progress in maps generally increase as you head into higher levels of the map.
Demoman Jump maps
Demoman jump maps are maps that require the Demoman to use his Sticky Launcher to sticky jump past obstacles and across wide gaps. In regular maps, sticky jumping has the drawback of you having to take more damage than rocket jumping; however, in most jump servers, that issue is combated with plugins that dispense health and ammo as you take damage. This is limited to two stickies as three stickies will kill you faster than the server's dispensing. Advanced sticky jumping tends to be much more difficult than rocket jumping. For example, when performing a rocket pogo you generally hold down the fire button. When pogoing as a Demoman, you cannot simply hold down the fire button; rather, you must take account where you fire and when you detonate the sticky. Much like doing a Soldier jump map, you must have knowledge of how to perform various methods of sticky jumping, and the level of difficulty generally increases as you progress in the map.
Scout Jump maps
Scout jump maps are a little different than Soldier or Demoman jump maps. Instead of using an explosive to propel yourself through obstacles, a Scout will be forced to utilize double jumps and the Force-A-Nature (and its related "triple jump" and "Force jump") to get across the map. Many of these maps rely less on progressing long distances with single jumps and more on the precise use of jumps, direction, and rate of movement to cross smaller, more complicated obstacles.
Engineer Jump maps
The Wrangler released with the Engineer Update allows Engineers to Sentry Gun/rocket jump using their Sentry Gun rockets. As an Engineer, you can maneuver in the air by the use of air strafing, however, the issue comes with where you put your rockets or bullets in order to propel yourself. It is more difficult to perform simple jumps than as Demoman or Soldier as you have less control over the placement of projectiles especially with the use of bullets in open air. Ammunition becomes a problem if the sentry is in a place you cannot easily reach. Practicing with Engineer jumping usually solves problems of imprecise jumping.