One of the biggest concerns for prospective Japanese learners is mastering a new writing system - or three to be precise. Though memorising the multiple meanings and pronunciations of the thousands of unique kanji to the point of quick recognition (for reading) and recall (for writing and speaking) will take the average learner months if not years of dedication (unless they have the significant advantage of knowing the Chinese - particularly Chinese Traditional - writing system), the other two systems used in Japanese writing are pleasingly straightforward.
Hiragana and katakana (collectively 'kana') are the two writing systems used primarily for words of Japanese and other non-Chinese origins. While at 46 characters each they are larger than the 26-letter Latin alphabet, there are a few reasons the two writing systems are much simpler to master than you might think.
Hiragana and katakana are syllabaries, meaning their characters represent single syllables rather than individual sounds. However, while Japanese is like the Latin alphabet in that it has five vowels, Japense differs from most Latin languages in that it has just five different vowel sounds: rather than having a variety of different 'a', 'e', 'i', 'o' and 'u' sounds based on context, they remain consistent throughout the language. Further, all but one of the 46 syllables are the vowels alone or the vowels preceded by one of 10 different consonants: 'k', 's', 't', 'n', 'h', 'm', 'y', 'r' and 'w' (note 'w' and 'y' don't combine with all vowels, hence the total of only 46 characters rather than 56). The only outlier is 'n', which can appear without preceding a vowel.
In addition to this highly structured nature of Japanese syllables, things are made easier by the fact that the two syllabaries contain the same 46 main kana. Hiragana and katakana are - for the most part - just two different ways of representing the same set of syllables.
I say '46 main kana' as there are complexities introduced via dakuten (linguistically close to voicing) and handakuten (the opposite), plus yōon which combine some characters together, but these are all still fairly consistent in how they work, and act mostly as well-defined modifiers to the kana.
An additional complication is that 'shi', 'chi', 'tsu', 'fu', 'ji' and more are thrown in there to haunt those of us who love hyperconsistency, and the katakana have a few extras to accommodate sounds from other languages, but these are minor qualms next to the giant task of learning kanji.