In Europe, we use comma for separating decimals and a dot or just a blank space as a thousands separator. In case you will notice the following on an invoice or VAT report: 10.000,56 EUR, it means you must pay ten thousand euros and fifty-six cents.
The UK system is different though and is similar to the US one.
Examples of number formats:
Most European countries (as well as our systems):
100.000 or 100 000 means one hundred thousand
10.000,99 or 10 000,99 means ten thousand and ninety-nine cents.
The UK(as well as the US, Australia, and New Zealand):
100,000 means one hundred thousand
10,000.99 means ten thousand and ninety-nine cents.