Description
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Created by ayush verma
over 6 years ago
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Page 1
1. Placing scripts at the bottom of the <body> element improves the display speed, because script compilation slows down the display. 2. External scripts cannot contain <script> tags. 3. JavaScript uses the var keyword to declare variables. 4. All JavaScript identifiers are case sensitive. 5. In javaScript,you can declare many variables in one statement. E.g. var person = "John Doe", carName = "Volvo", price = 200; 6. A variable declared without a value will have the value undefined. 7. If you re-declare a JavaScript variable, it will not lose its value. 8. If you put a number in quotes, the rest of the numbers will be treated as strings, and concatenated. E.g. var x = "5" + 2 + 3; Here, x stores the value 523. 9. JavaScript evaluates expressions from left to right. 10. In JS, arrays are defined as: E.g. var cars = ["Saab", "Volvo", "BMW"]; Array indexes are zero-based, which means the first item is [0], second is [1], and so on.
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