If you’re interested in the history and rationale behind Chinese characters, Zompist has a wonderful exposition based on the English language:

Maybe there’s a better approach. Instead of using hanzi directly, let’s invent a new system— we’ll call it yingzi, “English characters"— that would work for English exactly as hanzi works for Chinese.

The basic principle will be, one yingzi for a syllable with a particular meaning. So two, to, and too will each have their own yingzi. (If we were creating a syllabary, by contrast, we’d write all three with the same symbol, the one for /tu/.)

Does that mean we need a completely separate symbol for each of the thousands of possible English syllables? Not at all. We can simplify the task enormously with one more principle: syllables that rhyme can have yingzi that are variations on a theme.

It sounds a bit fanciful, but that’s exactly how Chinese characters came about. Have a look at the text—and the pictures—and things might become clearer.