Depending on what your concerns and problem areas are, there are different ways that the abdomen can be rejuvenated.
Liposuction– Occasionally the abdominal skin can collect deposits of adipose tissue (also known as fat). Liposuction can be used to remove this tissue. It is important to note however that liposuction only works if your skin is tight and of good quality. Liposuction does not fix loose skin, especially if there are stretch marks. Additionally, liposuction can make cellulite worse and should not be used as a tool for weight loss.
Mini-tummy tuck- A mini-tummy tuck involves cutting out loose skin on the lowest part of the abdomen (around where a C-section scar would be). It does involve the creation of a lower abdominal scar that is much longer than a C-section scar. A mini-tummy tuck generally does not fix any loose skin above the belly button or any rectus diastasis (where the rectus muscles have split, usually after childbirth).
Full tummy tuck (aka abdominoplasty)– This involves making a cut along the lower abdomen and around the belly button so that all the skin can be lifted off the abdominal wall. Once this is done, any gap in the rectus muscles is repaired. Excess skin is then amputated (usually this means cutting off all the skin up to the bellybutton) and then the remaining skin is stretched down to close the belly. A hole is then made for the belly button to come out through. This leaves a scar along the lower abdomen slightly longer than a mini-tummy tuck scar and a scar around the belly button. A full abdominoplasty results in tighter skin both below and above the belly button in addition to flattening and tightening the belly through muscle repair.
As with any procedure, it is important to discuss your goals with a board certified plastic surgery in order to better understand what each option can address, as well as their limitations and possible complications.