Angels are often portrayed as being something wonderful and beautiful. However, the images of death angels are anything but that. They are often a symbol of darkness and blackness there to take a life even if it isn't ready to let go yet. The pictures of the death angels are often very dark and scary. They may be of a skeleton or some other dark creature that you know instantly doesn't come for something good.
The term grim reaper is very often associated with death angels. Many people began looking more into this after the movie Meet Joe Black was released starring Brad Pitt. The beliefs that society have about death angels are very different from one culture to the next. Some view it is another part of the process of life, a necessary transition. Others view it as something to be feared.
This fear is believed to be the result of humans knowing that death is inevitable. It doesn't matter how successful or poor you are. Everyone will suffer that same fate at some time. The fear is also the result of so many people losing someone they love. They certainly aren't ready for it to happen. They may feel that they have been cheated of the time with that person due to the death angels.
For some people though, death angels can be something comforting. For example a person that has been suffering due to an illness is finally at peace. The death angels are believed to come and take the spirit of that person to heaven with them. It can be hard to let that person go but at the same time it is believed to be exactly what they need to rest peacefully. This is often a type of understanding of death that comes with being older and wiser.
There are plenty of references to the death angels in our society though. For example there are movies, art, books, and even video games that portray it. Generally it is associated with something evil. In the movie Ghost with Patrick Swayze the death angels are those that come for the bad people that die. They are dark black images that take the person off screaming in horror.