Death is that the permanent cessation of all biological activity that sustains an organism.  Typical death cases include aging, hunting, malnutrition, disease, suicide, murder, starvation, dehydration, and major trauma caused by accidents or terminal injury.  In most cases, the bodies of organisms begin to decompose shortly after death. 
Almost all animals that shake external dangers to their biological function eventually die from the biological age, which is named “senescence” in bioscience . Some organisms experience little or no maturity and even exhibit biological immortality. These include jellyfish Turidopsis dohrni,  hydra, and planarian. Unnatural causes of death include suicide and poaching. For all reasons, about 150,000 people worldwide die a day .  of those , two-thirds die directly or indirectly, but in industrialized countries – like the us , the uk and Germany – the speed approaches 90% (ie, nearly nine out of nine deaths are related to senescence). 
Physical death is now viewed as a phenomenon: the conditions that were alleged to point to death are now reversible.  Drawing a line between life and death within the process depends on factors beyond the presence or absence of important signs. Generally, medical death isn’t necessary or sufficient to work out legal death. A patient with a working heart and lung could also be declared legally dead without causing medical death. As knowledge domain and medicine progresses, it’s very difficult to determine an accurate medical definition of death. 
Signs of death or strong signs that a warm-blooded animal is not any longer alive:
Respiratory arrest (not breathing)
Heart block (no pulse)
Brain death (no neurological function)
Balor Mortis, a pale pastor that happens within 15-120 minutes of death
Alcor Mortis, Decrease in blood heat following death. this is often usually a gentle decline as long because it matches the ambient temperature
Ricor Mortis, the limbs of the body become stiff (Latin rigid) and difficult to maneuver or manipulate
Liver Mortis, which places blood within the lower (proximal) a part of the body
Putrefaction, early signs of decay
Decay, reduced to simple sorts of matter, with a robust , unpleasant odor.
The skeleton, the top of the decay, where all the soft tissue decomposes and leaves only the skeleton.
Fossilization, the natural defense of skeletons, has long been evolving
Problems of definition
The concept of death may be a key to human understanding of this phenomenon.  There are many scientific approaches and different interpretations of the concept. additionally , with the arrival of survival therapy, also as many criteria for outlining death from a medical and legal standpoint, it’s difficult to develop one unifying definition.
One of the challenges in defining death is to differentiate it from life. As a phase of your time , death marks the top of life. it’s difficult to work out when death occurred, as life functions are often not concurrent in organ systems.  Such a resolution must therefore draw a particular ideological boundary between life and death. this is often difficult because there’s no consensus on the way to define life.