Firstly, the Japanese Language and the Chinese Language is not of the same linguistic family, thus there will be a large number of differences.
Pronunciation:
Japanese consists of syllables called mora and consists of a consonant cluster plus a vowel. Several mora make a "word" in Japanese. In contrast, Chinese is broken down by character, which each character is given at least one reading of exactly one syllable long. Chinese also distinguishes between tone in all its dialects; Japanese does not and uses a tone-based stress to clarify what is being said.
Writing System:
It is in this manner the Japanese developed kanji, the Chinese characters used in Japanese.
Japanese uses three different scripts, not counting Roman Letters and Arabic Numerals, in everyday writing: kanji, hiragana and katakana. Kanji, as noted, is the Chinese characters seen in Japanese text. Hiragana and Katakana are symbols derived from grass script calligraphy of Chinese characters and evolved to be their syllabary. Chinese only uses Chinese characters.
Vocabulary:
Japanese also imported a large amount of vocabulary when importing Kanji from the Chinese. This gave two results: many distinctively Chinese concepts retained their Chinese reading, while many of the Japanese concepts gained a kanji which meant what the kanji represented in Chinese. Aside from these similarities, there is almost no point in common between the vocabulary of the two languages.
Grammar:
Japanese and Chinese employ two completely different grammar schemes - first, even the order of the sentence would not be the same in the two languages: Chinese is mainly Subject - Verb - Object, like English (Although it is technically possible to construct a sentence meaning exactly the same thing using a different order) and Japanese is always Subject - Object - Verb, like German most of the time. Japanese also possess a past tense (but no future tense) while Chinese does not distinguish the tense at all.
Japanese and Chinese are similar in some aspects yes. The Japanese took Chinese characters for their third alphabet. They are both dirived from a non-latin basis. They are vocal and pitch related.
Chinese and Japanese are not related to any common ancestor:
They are related in the sense that Japanese uses many Chinese characters in it's writing system.
Much of the Japanese written language is based on kanji. The Kanji came from China. The Japanese then added Katakana and Hirakana to provide additional ways of writing.
Japanese and Chinese written language share some characters known as Han Zi. Japanese also uses Kanji that is not used in Chinese. Modern Chinese is read from left to right and top to bottom (like English). Japanese is not.
The japanese first borrowed from the Chinese. Then they simplified the chinese characters into the 50 'kanas'
The name Lulu is written in Chinese as Lu Lu. This name is written in the Japanese language as Ruru.
Japanese language uses 2 alphabets (hiragana and katakana) in addition to more complex characters that are derived from the Chinese written language. Kanji (Japanese characters) are the same as Chinese characters.
Ki is a Japanese word, which is written with Chinese characters. See related link..
Tadachika Takada has written: 'Rikutai Senjimon' -- subject(s): Calligraphy, Chinese, Chinese Calligraphy, Chinese Primers, Primers, Chinese 'Gakko happan' -- subject(s): Chinese Inscriptions, Chinese language, Etymology, Inscriptions, Chinese 'Kanji shokai' -- subject(s): Etymology, Japanese language, Chinese language
Jo-ming Lu has written: 'Sosho dictionary' -- subject(s): Chinese language, Japanese language, Writing
Thomas Innes was a Scottish historian who is known for his book "Critical Essay on the Ancient Inhabitants of the Northern Parts of Britain or Scotland". In this work, he discussed the history of Scotland and its ancient inhabitants.
Tokyo Sanseido has written: 'Kanwa daijiten' -- subject(s): Dictionaries, Chinese language, Japanese
There is no alphabet in the Chinese language, unlike English or even Korean or Japanese (and even Korean and Japanese have no set order for their 'alphabet'), as Chinese language is simply written with different strokes put together. You might find websites that give you the way English alphabets might be written in Chinese, phonetic-wise, but that is only how we would pronounce English alphabets in Chinese phonetically, and not the Chinese alphabet. :)
They have similarities, because Japanese written language is mostly based on Chinese. The Japanese use around 2000 symbolic characters called Kanji, which each represent a full word or concept and are directly borrowed from Chinese. Unlike Chinese though they also have a phonetic text which can be written two ways depending on the exact word. These are called Katakana and Hiragana, and are more of an alphabet-based way of writing things, useful for imported words.