1. Avoid using Equal(==) and not equal(!=)
These operators can do type coercion(e.g. “”==false will evaluate to true )
It is better to use === and !==, which do not do type coercion.
It is ambiguous.Please check this blog for details
The only exception is when you parse JSON.However, you need to completely trust your server which you should not.
There are several JSON parser you can find in JSON
Most recent browser (at the time of writing IE8,FireFox 3.5,Chrome 3) support native JSON Parsing.For more info, Check here
0.1 + 0.2 = 0.30000000000000004
5. Style Isn’t Subjective
Check this ppt slides for details.
An Inconvenient API: The Theory of the Dom