1+ //JavaScript variables can hold different data types: numbers, strings, objects and more, there are a lot of data types.
2+ let length = 16 ; // Number
3+ let lastName = "Johnson" ; // String
4+ let x = { firstName :"John" , lastName :"Doe" } ; // Object
5+
6+ //Javascript is not a statically types language, therefore you can add different data types to each other
7+ //for example:
8+
9+ let number = 5 ;
10+ let text = "test"
11+ let result = number + text ;
12+ //this will result in '5test'
13+ //since the number variable is converted to string before the addition
14+
15+ //JavaScript evaluates expressions from left to right. Different sequences can produce different results:
16+
17+ let x = 20 + 5 + "New Text"
18+ //This will result '25New Text'
19+
20+
21+ //Also Javascript types are dynamic
22+ //So you can do things like
23+
24+ let variable ;
25+ variable = 105 ;
26+ variable = "Name"
27+ variable = false ;
28+
29+
30+ //You can write strings with both double (") and single (') quotes and also if you write string templates, you can use backtics (`)
31+ let string1 = "string1"
32+ let string2 = 'string2'
33+ let stringe = `string3`
34+
35+ //There are also numbers, where you can choose to write decimals or not
36+ //such as
37+
38+ let number1 = 15 ;
39+ let number2 = 15.00 ;
40+
41+ //or you can write numbers with scientific notation:
42+ let y = 123e5 ; // 12300000
43+ let z = 123e-5 ; // 0.00123
44+
45+ //Booleans
46+ //there are 2 values for booleans, true and false
47+ let bool1 = true
48+ let bool2 = false
49+
50+ //you can use operators on other datatypes in order to return boolean values
51+
52+ let bool3 = 5 < 6 //true
53+ let bool4 = 2 ^ 2 == 3 //false
54+
55+ //Arrays
56+ //you can initiate arrays with `[]`
57+
58+ let array1 = [ 1 , 2 , 3 ]
59+ //or make empty arrays:
60+ let array2 = [ ] ;
61+
62+ //arrays can contain different data types
63+
64+ let array3 = [ 1 , "true" , false ]
65+
66+ //Objects are written like
67+ //they're very similar to how JSON is stored.
68+ const person = { firstName :"John" , lastName :"Doe" , age :50 , eyeColor :"blue" } ;
69+
70+
71+ //source gathered from https://www.w3schools.com/js/js_datatypes.asp
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