An ancestor is someone who you directly descend from. I have seen definitions that say this begins at your parents, but in the world of genealogy, we often refer to anyone before our grandparents as ancestors (great grandparents and earlier). Since you do not descend directly from you aunts, uncles, and cousins, they are not your ancestors. They are, however, your relatives.
You have two types of ancestors: maternal and paternal. Maternal ancestors are those on your mother’s side, and paternal ancestors are those on your father’s side. Your mother’s parents are your maternal grandparents, and your father’s parents are your paternal grandparents.
Some genealogists prefer to concentrate only on their ancestors while others enjoy researching as many blood lines as they can find. Personally, I prefer the latter. I find that the more branches I research, the more distant cousins I come across in life, which, for me, is one of the most exciting parts of genealogy. I keep in regular contact via e-mail with a couple of “long-lost” cousins, and there are more that I have met (either in person or online), and lost contact with, through the years. They have helped me fill in some gaps in my genealogy, and I have helped them with the same.
If you are just starting out, however, I do recommend that you begin with your direct ancestors only. Trying to research every name you come across can overwhelm you. In addition, it can take away from the joy and excitement that genealogy research can bring. If you wish, you can start including distant relatives to your research as you progress and become more comfortable with your research. Doing so may help unlock missing information about your direct ancestors, and as I mentioned earlier, may lead you to distant relatives who are also researching common ancestors.
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