Around Halloween the Grim Reaper character is often depicted in decorations and costumes. It consists of a shadowy character hidden in a black cloak, holding a scythe, ready to reap the "harvest" of a dead person's soul.
While in general the Grim Reaper is a personification of death, the imagery may have been influenced by the Book of Revelation.
Death as the Fourth Horseman
The Book of Revelation features Death as one of the four horseman of the Apocalypse.
Death is given a haunting visual in this passage, and is depicted in a way similar to the way the Grim Reaper pursues the dying.
The harvest of death
Later in the Book of Revelation, the death and judgment of individuals is depicted as a harvest, including a sickle, which is a smaller version of a scythe used in harvesting crops.
In some depictions the Grim Reaper is wearing a crown, and may be a direct reference to this scene in the Book of Revelation.
While there are many other influences behind the Grim Reaper, much of the symbolism can be found in the Bible.