Simplified Chinese (actually the written form of simplifed Chinese characters) is mostly used in mainland China, Singapore and Malaysia. Traditional Chinese (meaning traditional/complex Chinese characters) is, on the other hand, mostly used in Taiwan, Hong Kong SAR, Macau SAR, and among some overseas Chinese populations. Nonetheless, the two variants are mutually understandable to the majority of Chinese.
People may become confused when comparing Simplified Chinese (written form) to spoken dialects (for example, Mandarin, Cantonese, Min Nan, Hakka, and Wu). Those who use Simplified Chinese characters may speak any of the above-mentioned Chinese dialects, likewise, those who use Traditional Chinese characters can also speak any of the above-mentioned Chinese dialects. The written version of the Chinese language (whether in simplified characters or traditional/complex characters) shares many similiarities, although spoken dialects vary greatly depending on where you reside.
We have native Mandarin, Cantonese speaking lawyer-linguists/legal translators to assist with your Simplified Chinese language needs.