Though there are still debates about assisted suicide and euthanasia, but in some countries this practice is legalized by law. For you whom still confuse about assisted suicide and euthanasia below are some short explanation about it.
Assisted suicide is a self-induced death. The means (drugs or other devices) which cause such a death are provided by a second agent. It could be a doctor or another individual. Although a legal distinction is made between euthanasia and assisted suicide, there is no ethical difference.

It remains a criminal act to counsel, aid or abet a suicide because historically it was recognized that those who consider suicide are especially vulnerable to those who could take advantage of them. It was also recognized that it was impossible to enforce any kind of “limited” assisted suicide and euthanasia without opening the door to all kinds of abuse.

Euthanasia means acting or failing to act in such a way as to cause the death of another human being, where the primary intention is to kill, supposedly for his or her own good. No matter what the reason or method, killing is killing. Euthanasia and assisted suicide is saying: We think you would be better off dead.
Euthanasia and assisted suicide advocates present the practice of having someone “assist” in the death of another as an exercise in compassion. They present killing as an act of mercy–hence the term “mercy killing”. It is no kindness or mercy, however, to kill the suffering individual. Compassion does not seek to eliminate the sufferer. For ages, our society has recognized that a request for death was a cry for help.