1. GB is the Chinese Pinyin acronym of the word "National Standard", which means "China's National Standard", referred to as "National Standard".

2. GB/T is the recommended standard under the national standard. t is the abbreviation of "Tui" in Chinese Pinyin, which means "recommended national standard".

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3. GB is a mandatory standard, approved and issued by the national standardization authority, and enforced nationwide. They are standards for safeguarding human health, personal and property safety, and national standards enforced by laws and administrative regulations. The national standard number consists of the national standard code, serial number and publication year.

4. GB/T is a recommended standard (voluntary standard), which is also approved and issued by the national standardization authority, and is recommended to be implemented nationwide. They are national standards voluntarily adopted by economic means or market regulation in production, exchange and use.