Hiragana is curvilinear and is used to write certain Japanese words, such as particles (wa, ga, ni), conjunctions, certain nouns and so on. Hiragana suffixes are also used with kanji stems to form verbs and adjectives.

They are an essential part of the Japanese written language and, seeing as there's only 46 basic hiragana, most written with only two or three strokes, it's a good idea to get them under your belt before embarking on the kanji.