The WAVES were women who served in the United States Navy during the Second World War. These women had equal status with their male Navy counterparts, serving primarily in the United States to free up male members of the Navy for postings overseas. Towards the end of the war, some of the WAVES were also dispatched to other postings in places like Hawaii, but they were kept out of combat positions. The restriction which prevents women from serving in combat positions persists to this day, although an increasing number of positions in the military are open to women.
WAVES is, of course, an acronym, which stands for “Women Accepted for Volunteer Emergency Service.” Eleanor Roosevelt was a champion of the WAVES, and it was she who pushed Congress to establish this division of the Navy, allowing women who wanted to enlist to do so, and offering them full Navy pay and other benefits. In 1942, Mildred McAfee became the first female commissioned officer in the history of the Navy, and the WAVES was born.
In contrast with the WAVES, the Army had the Women's Auxiliary Army Corps (WAAC), which was an auxiliary organization, associated with the Army but not fully in it. While WAVES and WAACs performed many similar tasks, it wasn't until 1943 that the WAAC became the Women's Army Corps, according women more equal footing in the Army.
While WAVES didn't perform combat-related tasks, they did do a number of other things, setting the stage for the Women's Armed Service Integration Act of 1948, which allowed women to serve as regular members in the United States armed forces. Prior to this act, women could only serve in the military on a provisional basis; the WAVES, for example, were supposed to be dissolved after the Second World War.
The British military also had similar opportunities for women who wished to serve during the course of the war, and many women in the WAVES and their counterparts like the Women's Royal Naval Service distinguished themselves during the course of the war. Some women who served on a provisional basis during the war went on to become career members of the military, and the presence of women in the military has continued to grow; in 2008, the first female four star general was nominated, an extremely significant event in military history and a sign that the brass ceiling might be crumbling.