The maximum value of a float is about 3.4*1038, which isn't large enough for some things you might wish to represent, such as the number of electrons in the universe.

float的最大值约为 3.4*1038。 这个值还不足以表示某些东西，比如宇宙中的电子数目。

youdao

Well basically what we're doing is we're giving ourselves the ability to create data types the same way that we have some built-ins, so we have things like int, float, string, these are built-in data types.

就是要赋值我们自己创建,和内置的数据类型,相同的数据类型的能力,我们有一些内置的数据类型，如int，float，string等，如果你考虑下这些数据类型。

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