JavaScript an object-oriented computer programming language commonly used to create interactive effects within web browsers. The basics of JavaScript are given in this ppt.

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Practices of JavaScript
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Avoid Global Variables
 Minimize the use of global variables.
 This include all data types, objects, and functions.
 Global variables and functions can be overwritten by other scripts.
 Declare local variables with let and const.

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Practices of JavaScript
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Use === instead of == for comparison

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Practices of JavaScript
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Don’t use new object ()
 Use “ ” instead of String()
 Use O instead of new Number()
 Use false instead of new Boolean()
 Use { } instead of new object()
 Use [ ] instead of new Array()
 Use /()/ instead of new RegExp()
 Use function () { } instead of new Function()

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Practices of JavaScript
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Example

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Practices of JavaScript
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eval() usage is Bad
The eval() function is used to run text as code. In almost all cases, it should not be
necessary to use it because it might cause a security problem.

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Practices of JavaScript
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Create helper functions for common tasks

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Practices of JavaScript
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Use for…of instead of for loops

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Practices of JavaScript
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Other Tips
 Give descriptive purposeful names to variables and
functions (Use camel case capitalization often).
 Put JavaScript in a separate file.
 Put Scripts at the bottom of your page.
 Use JSLint.