A little context on the Japanese Alphabet(s) The japanese Alphabet(s) differ greatly from the alphabets of the Romance Languages (that is english, french, spanish, etc). The first obvious difference is that their is not one alphabet, but rather two (and kanji, but I'll get into that later). The second difference is that rather than "letters" specifying a particular sounds (like in english) the letter are more akin to what romance speakers would call vowels. This is why there are considerably more letters (about 42) for each alphabet.
Hiragana
The above Alphabet (Hiragana) is the "primary" alphabet. Hiragana is used for most words that don't have a specific Kanji. Katakana (below) is mostly used for loan words/ more technical words.