The particle の can be used at the end of a sentence to seek explanation, clarification or confirmation about something.
When の is used after a noun or a な-adjective, the noun or adjective is suffixed with な.
When used at the end of a statement, の can indicate the speaker is giving an explanation, often with an emotional or emphatic nuance.
の can also be used to make statements or questions sound softer, more indirect, or less assertive. This is especially common in feminine speech, though not exclusively so.
Lastly, の can be used to add emphasis or a sense of emotion to a statement. This usage is similar to using よ at the end of a sentence. Using の at the end of a sentence emphasizes your feelings and makes you assert yourself in a soft, indirect manner. This usage is more common among females, though not exclusive to them. Using よ at the end of a sentence emphasizes or asserts new information, making sure the listener acknowledges and takes note. It is more direct than の.