Using "and" in number words.
One of the most common questions in writing numbers out: does "and" belong inside the number? The short answer is that it depends on which side of the Atlantic you're on — and on whether you're crossing a decimal point.
The British convention
British English places "and" before the final tens and units in a number. So 101 is "one hundred and one", 250 is "two hundred and fifty", and 1,234 is "one thousand, two hundred and thirty-four". To a British reader, leaving the "and" out looks clipped or incomplete. Indian English follows the same convention, which is why this site's rupee output includes "and": 567 reads "Five Hundred and Sixty Seven".
The American convention
American usage traditionally reserves "and" for the decimal point — the boundary between whole and fractional. So 101 is "one hundred one", and 150 is "one hundred fifty". The "and" only appears when there's a fraction or cents: "one hundred and 50/100" on a check means one hundred dollars and fifty cents. This is why US check-writing guides are firm about it — an "and" in the wrong place can be read as a decimal that wasn't intended.
Which is correct?
Both are correct in their own region. The American "and only at the decimal" rule is a useful convention, especially in finance, but it's worth being honest: in everyday American speech, plenty of people say "one hundred and one" too. The strict rule is more a formal-writing and math-teaching standard than a hard description of how everyone talks. What matters is consistency within a document and matching the expectation of your reader.
How the converter handles it
Rather than make you choose, this site sets the "and" automatically from the currency: rupees, pounds and euro use the British style ("and" included), while dollars use the American style ("and" omitted inside the number, reserved for the cents fraction). You can see the difference by switching currency on the currency converter — 101 reads "One Hundred and One" in GBP and "One Hundred One" in USD.