15. The computer-readable medium of claim 13 , wherein determining the particular language comprises: determining a particular market based on a top-level domain of a particular URL; determining whether the text is encoded in ASCII; determining whether only one language is mapped to the particular market in a stored set of market-to-language mappings; determining whether the top-level domain is within a specified subset of top-level domains that consists only of “cn,” “tw,” “jp,” “kr,” and “hk”; and in response to determining that (a) the text is encoded in ASCII, (b) more than one language is mapped to the particular market in the stored set of market-to-language mappings, and (c) the top-level domain is within the specified subset of top-level domains, determining that the particular language is English.
13. A volatile or non-volatile computer-readable storage medium storing one or more instructions which, when executed by one or more processors, cause the one or more processors to perform steps comprising: determining a particular language based at least in part on both content of text submitted by a user and a source IP address that is associated with the user; and based on having determined the particular language for the user, presenting, to the user, one or more content items that are associated with the particular language; wherein the content of the text does not expressly state the particular language.