In 1917 and 1918, approximately 24 million men registered for the draft in the United States. These included me born from September 11, 1872 (they would have been 45 years of age) to September 12, 1900. Not everyone who registered, served. These draft registrations are a wonderful resource as it lists a lot of information:
As you can see, we get to see their birthplace, name and place of employment, home address, name of nearby relative, their physical build size and hair and eye color. It is a great snapshot of the family members at that point in time.
Here is the Draft Registration of Ezra James Riley (son of Thomas and Lizzie):
We can see that he was married and had one child. He worked as an Hot Mill Worker at American Sheet and Tin in Dover Ohio. Was listed as tall and slender with Blue eyes and brown hair. He was 21 at this time and was natural born in Pennsylvania. As you can see, this is a great help in genealogical research.
I'll be sharing many more of these in the future.