There are standards, but like all standards there are multiple to choose from and at least one major non-standard. In the US, the big ones are Tesla, CCS, and C

There are standards, but like all standards there are multiple to choose from and at least one major non-standard. In the US, the big ones are Tesla, CCS, and CHAdeMO, in roughly that order of popularity. Its a bit like Diesel vs E85 vs premium vs plus vs regular, except with the added mix of having one branded version. Tesla's is largely the result of getting this stuff figured out back in 2012. Back then, standardization wasn't really an option.