2018-10-12 15:37:13 -04:00 
										
									 
								 
							 
							
								
							 
							
								 
							
							
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								title: Functions List
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
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								JavaScript (JS) is a lightweight, interpreted, programming language with first-class functions. Most well-known as the scripting language for Web pages, many non-browser environments also use it, such as < a  href = 'https://nodejs.org'  target = '_blank'  rel = 'nofollow' > node.js< / a >  and < a  href = 'http://couchdb.apache.org/'  target = '_blank'  rel = 'nofollow' > Apache CouchDB< / a > . JS is a prototype-based, multi-paradigm, dynamic scripting language, supporting object-oriented, imperative, and declarative (e.g. functional programming) styles.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								JavaScript runs on the client side of the web, which can be used to design / program how the web pages behave on the occurrence of an event. JavaScript is an easy to learn and also powerful scripting language, widely used for controlling web page behaviour.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								Checkout < a  href = 'https://developer.mozilla.org/en-US/docs/Web/JavaScript'  target = '_blank'  rel = 'nofollow' > MDN's JavaScript Docs< / a > , they are a great asset in learning.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								We also have some great articles on our wiki:  
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/advantages-and-disadvantages-of-javascript/14280'  target = '_blank'  rel = 'nofollow' > Advantages and Disadvantages of JavaScript</ a >    
						 
					
						
							
								
									
										
										
										
											2019-01-05 12:33:30 -08:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
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								**JavaScript Data Types:** 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
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											2018-10-12 15:37:13 -04:00 
										
									 
								 
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-boolean/14311'  target = '_blank'  rel = 'nofollow' > Booleans</ a >    
						 
					
						
							
								
									
										
										
										
											2019-01-05 12:33:30 -08:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
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								**JavaScript Strings:** 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
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											2018-10-12 15:37:13 -04:00 
										
									 
								 
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-string-prototype-charat/15932'  target = '_blank'  rel = 'nofollow' > String.prototype.charAt()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-string-prototype-charcodeat/15933'  target = '_blank'  rel = 'nofollow' > String.prototype.charCodeAt()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-string-prototype-concat/15935'  target = '_blank'  rel = 'nofollow' > String.prototype.concat()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'https://forum.freecodecamp.org/t/javascript-string-prototype-indexof/15936'  target = '_blank'  rel = 'nofollow' > String.prototype.indexOf()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/string-prototype-lastindexof/15939'  target = '_blank'  rel = 'nofollow' > String.prototype.lastIndexOf()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-string-prototype-match/15941'  target = '_blank'  rel = 'nofollow' > String.prototype.match()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-string-prototype-replace/15942'  target = '_blank'  rel = 'nofollow' > String.prototype.replace()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-string-prototype-slice/15943'  target = '_blank'  rel = 'nofollow' > String.prototype.slice()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-string-prototype-split/15944'  target = '_blank'  rel = 'nofollow' > String.prototype.split()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-string-prototype-substr/15945'  target = '_blank'  rel = 'nofollow' > String.prototype.substr()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-string-prototype-substring/15947'  target = '_blank'  rel = 'nofollow' > String.prototype.substring()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-string-prototype-tolowercase/15948'  target = '_blank'  rel = 'nofollow' > String.prototype.toLowerCase()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-string-prototype-touppercase/15950'  target = '_blank'  rel = 'nofollow' > String.prototype.toUpperCase()</ a >    
						 
					
						
							
								
									
										
										
										
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								**JavaScript Arrays:** 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
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								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-isarray/14284'  target = '_blank'  rel = 'nofollow' > Array.isArray()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-concat/14286'  target = '_blank'  rel = 'nofollow' > Array.prototype.concat()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-every/14287'  target = '_blank'  rel = 'nofollow' > Array.prototype.every()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-filter/14289'  target = '_blank'  rel = 'nofollow' > Array.prototype.filter()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-foreach/14290'  target = '_blank'  rel = 'nofollow' > Array.prototype.forEach()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-indexof/14291'  target = '_blank'  rel = 'nofollow' > Array.prototype.indexOf()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-join/14292'  target = '_blank'  rel = 'nofollow' > Array.prototype.join()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-lastindexof/14293'  target = '_blank'  rel = 'nofollow' > Array.prototype.lastIndexOf()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-map/14294'  target = '_blank'  rel = 'nofollow' > Array.prototype.map()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-pop/14296'  target = '_blank'  rel = 'nofollow' > Array.prototype.pop()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-push/14298'  target = '_blank'  rel = 'nofollow' > Array.prototype.push()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-reduce/14299'  target = '_blank'  rel = 'nofollow' > Array.prototype.reduce()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-reverse/14300'  target = '_blank'  rel = 'nofollow' > Array.prototype.reverse()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-shift/14301'  target = '_blank'  rel = 'nofollow' > Array.prototype.shift()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-slice/14302'  target = '_blank'  rel = 'nofollow' > Array.prototype.slice()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-some/14304'  target = '_blank'  rel = 'nofollow' > Array.prototype.some()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-sort/14306'  target = '_blank'  rel = 'nofollow' > Array.prototype.sort()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-splice/14307'  target = '_blank'  rel = 'nofollow' > Array.prototype.splice()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-tostring/14308'  target = '_blank'  rel = 'nofollow' > Array.prototype.toString()</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-array-prototype-unshift/14309'  target = '_blank'  rel = 'nofollow' > Array.prototype.unshift()</ a >    
						 
					
						
							
								
									
										
										
										
											2019-01-05 12:33:30 -08:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
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								**JavaScript Loops:** 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
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											2018-10-12 15:37:13 -04:00 
										
									 
								 
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-loops/14681'  target = '_blank'  rel = 'nofollow' > Loops</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-while-loop/14668'  target = '_blank'  rel = 'nofollow' > While Loop</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-do-while-loop/14662'  target = '_blank'  rel = 'nofollow' > Do While Loop</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-for-loop/14666'  target = '_blank'  rel = 'nofollow' > For Loop</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-for-in-loop/14665'  target = '_blank'  rel = 'nofollow' > For In Loop</ a >    
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								-  < a  href = 'http://forum.freecodecamp.com/t/javascript-for-of-loop/14671'  target = '_blank'  rel = 'nofollow' > For Of Loop</ a >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								Checkout our other articles on JavaScript: < a  href = 'https://www.freecodecamp.com/wiki'  target = '_blank'  rel = 'nofollow' > https://www.freecodecamp.com/wiki< / a > .