Mandarin is usually written with Simplified Chinese characters. Cantonese is usually written with Traditional Chinese characters. They're "the same characters",

Mandarin is usually written with Simplified Chinese characters. Cantonese is usually written with Traditional Chinese characters. They're "the same characters", but the simplified ones tend to replace certain shapes with simpler versions. From friends, one tends to phrase things somewhat differently between the two languages/dialects. A phrase in one of them sometimes sounds awkward when expressed with the most directly equivalent words in the other. So you've got some pretty good clues about whether the original author of a document was thinking in Mandarin or Cantonese when writing it. And also, it's a Chinese government document in Shanghai: almost certainly simplified Chinese characters representing Mandarin Chinese.