A killer is a person or thing that ends lives. The word can also be used to describe something that is severe or powerful.

The killer whale (Orcinus orca) is the largest member of the dolphin family and one of the most ferocious marine predators on the planet. These highly intelligent ocean creatures work together as a coordinated team, hunting as a unit and rarely losing a battle. They can be identified by their large black backs, medium-sized white patches above and behind their eyes, and a long, pointed, toothy jaw.

While there are many definitions of serial murder, most law enforcement agencies set a threshold of three or more murders over the course of more than a month with a significant time span between each killing. This number allows police to focus on a serial killer while still maintaining the flexibility to investigate other cases where there is reasonable suspicion of serial murder activity.

Most serial murders are committed as part of a pattern or a spree, but there are exceptions. Some of these cases involve a person suffering from mental illness who kills because of auditory and/or visual hallucinations, paranoid or grandiose delusions, and/or sexually-based motivations. Psychiatric and medical professionals often use the term psychopath to describe these individuals.

In the 20th century, many notorious serial killers received widespread media coverage, which helped to raise public awareness and spur debate about a variety of social and legal issues. These crimes were both horrifying and fascinating to the public, and some of these murderers became known by lurid nicknames such as the Boston Strangler, the Dusseldorf Vampire, and John Wayne Gacy. Their crimes raised questions about how thorough police were in investigating murder cases, the effectiveness of anti-crime laws, and the tendency to criminalize people who are poor or of lower social status.

Many killer whales are endangered due to overfishing and habitat loss. Additionally, these whales are at high risk of becoming entangled in fishing gear, which can cause them to drag and swim with the entanglement for extended periods of time, compromising their feeding and swimming ability. This can result in fatigue, injury, or death.

The popular podcast RedHanded, which is based on the book of the same name by Hannah Maguire and Suruthi Bala, uses real-life true crime stories to try to answer the question of whether or not serial killers are born or made. The show stars Ross Lynch as Jeffrey Dahmer and former Naked Brother’s Band actor-artist Alex Wolff as John “Derf” Backderf, who was a high school classmate of Dahmer before his serial killing began in 1978. The show attempts to provide a balanced look at the crimes of these murderers, but avoids the temptation to sympathize with them or attempt to understand their motivations for such heinous acts. This approach has helped to make the show a hit on all platforms. The ubiquity of smartphones has led to businesses across many industries seeking their own killer apps to drive digital and in-person traffic.