Exercises you will find in these videos will work your core and abs. Core and Abs are different and work within the body differently. It is advised that you do several of the videos so that you gain the most variety and train all of the important abdominal muscles.
Most people think of famous 6-packs when they are asked to imagine abs. But what abs or abdominal muscles really are is a prominent group of muscles (actually 6) in the anterior side of the belly, including oblique muscles. The main functions of abdominal muscles are assistance in breathing, spinal support during physical activity, and drawing the chest to the pelvis as well as maintaining internal organs of the abdomen in place. 6 abdominal muscles are placed in three layers that form the abdominal wall.
The notion of “core muscles” appeared not so long ago. This term is not included on the list of official anatomy terms. It is mainly used by fitness trainers or in the literature on sports and fitness to denote a number of muscle groups, mainly the torso muscles (all abdomen muscles, mid and lower back and glutes). It is necessary to mention that according to different authors the list of core muscles can be shorter or longer, but there is one thing common to each case: core muscles are engaged in body stabilization during any dynamic movement or when maintaining a difficult static position (such as plank).