Artificial life support are forms of medical technology used when your vital organ systems are failing. Examples include dialysis (removes toxins from your blood when your kidneys are not working); mechanical ventilation using a respirator (forces air in/out of your lungs using a tube when you cannot breathe on your own); feeding tubes (deliver liquid food and water directly to your stomach when you cannot swallow); and cardiac assist devices (assist the pumping action of your heart when your heart is failing).
Sometimes these technologies are used for the short term and you are expected to recover normal function, but sometimes people use these technologies as a permanent form of life support even if they have no cognitive function (e.g., a permanent coma/vegetative state). These patients live in nursing homes.
Long term use of artificial life support can have lots of side effects, including infection risk. Talk to your doctor about this and reflect on the risks and benefits when you write your Living Will/Advance Directive. For more information, read the book: Finding Your Way: A Medical Ethics Handbook for Patients and Families.