Which methods are the most prominent biochemical tests used in microbial identification?

There are various biochemical tests used for the identification of microbes. The most prominent ones are:
1. Phage Typing: This test is used to identify those bacteria that can be infected by viruses known as bacteriophage.
2. Gram's Staining: This method is used to distinguish between two broad categories of bacteria, Gram positive bacteria and Gram negative bacteria.
3. Carbohydrate Fermentation Test: This biochemical test is used to distinguish between bacteria that produce gas or not. 

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