The (*) means build the sensitivity list for me. For example, if you had a statement a = b + c; Then you'd want a to change every time either b or c changes. In other words, a is sensitive to.
Understanding the Context
The always @(*) syntax was added to the ieee verilog std in 2001. All modern verilog tools (simulators, synthesis, etc. ) support this syntax. Here is a quote from the lrm (1800-2009):
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