Katakana is mainly used for writing names or foreign loan words. An example would be テレビ (terebi) which means television. Hiragana is used a lot for grammatical purposes, such as wa (は) ga (が) and o (を). They both sound the same.
BTW, を is pronounced "wo" regularly, but when used grammatically, it becomes "o". Likewise, は is usually pronounced "ha" but is changed to "wa" when used grammatically.
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it's the same thing, サ is the katakana version of さ
Katakana is mainly used for writing names or foreign loan words. An example would be テレビ (terebi) which means television. Hiragana is used a lot for grammatical purposes, such as wa (は) ga (が) and o (を). They both sound the same.
BTW, を is pronounced "wo" regularly, but when used grammatically, it becomes "o". Likewise, は is usually pronounced "ha" but is changed to "wa" when used grammatically.