Whoa its been a hot minute since I posted any grammar. Sorry about that....
の is the ひらがな(hiragana) character pronounced "no." の can also be used as a particle which is a small word that goes on the end of words and phrases to indicate how they relate to other parts of the sentence.
Put simply, の connects two nouns.
の will have many uses that you will run into but we'll keep it simple today.
Hiragana: さくらさんのでんわばんごう。 Sakura's phone number
Romanji: Sakura san no denwa bangoo
English (lit): Ms. Sakura's telephone number.
Note: In this example の acts like 's would in English. But this isn't the only use. Let's look at more examples.
Hiragana: だいがくのせんせい A college professor.
Romanji: daigaku no sensee
Note: The second noun always provides the main idea while the noun before の elaborates or adds detail. In this case the first noun tells us that the teacher works at a college level.
Hiragana: にほんごのがくせい A student of the Japanese language
Romanji: nihongo no gakusee
Note: gakusee, or student, is the main idea. For this example the English translation has "student" come first in the sentence. In Japanese the main noun will always come at the end with the describing noun coming before it.
Romanji: watashi no okaasan wa kookoo no sensee desu
Translation: My mother is a high school teacher.
Note: A "noun の noun" phrase can fit into sentence structure as if it is one long noun. Notice that the particle は comes after the main idea verb.
Practice makes perfect! Its also the only way to learn another language. Try making a "noun の noun" phrase in the comments below! Even if you aren't sure its right give it a shot so that as a community we can learn!
Here's a few resources to help you along:
Hirigana/ Katakana Keyboard: http://www.lexilogos.com/keyboard/hiragana.htm
*Your computer also likely has the option to download a Japanese keyboard. It only takes 2 seconds to do!
More Practice!: http://web.lyon.edu/users/mpeek/JapanWebpages/GenkiExercises.htm
*This website is seriously great. Give it a try!