* Inquiries is the American English spelling.
* Enquiries is the British English spelling.
Both words mean the same thing: a request for information. They can be used interchangeably, but you should choose the spelling that aligns with the intended audience or style guide.
For example:
* American English: "I made some inquiries about the new product."
* British English: "He sent enquiries about the job opening."
Essentially, it comes down to whether you're writing for an American or British audience.