Other forms: someones
The word someone refers a person or an individual, but not necessarily a specific one. If you're not hungry enough for dessert after lunch, you can ask the friends at your table, "Does someone want my ice cream sandwich?"
It's a funny contradiction, but the noun someone can be used to mean "any unspecified person," but also "a very important person." So a child might say, "When I grow up, I want to be someone," meaning that they want to be well-known or famous, or just really good at something. Someone and somebody are synonyms, so you can use them interchangeably, although someone is slightly more formal.