The answer is: complicated. A slackline is an exercise and recreation activity that uses the same mechanism as a ratchet strap. They’re typically tied between two anchor points - traditionally trees. Slacklines differ from a tightrope because of the material they’re made of. Slacklines are made from the same material as ratchet straps. However, a slackline-specific strap is more heavy-duty than a standard ratchet strap. Additionally, slacklines can come with special loops on either end for securement purposes. A standard ratchet strap isn’t rated to support a body’s full weight. That said if you do buy a heavier-duty ratchet strap NEVER use ratchet straps you plan to use for cargo hauling for slacklining. You’re only wearing down the straps and making them unsafe for proper use afterward. If you want to try slacklining, purchase new straps specifically for the activity.