JavaScript Syntax and Type Conversion Quiz

Parameters and Data Types

• A parameter is a piece of data or an object that describes the characteristics of an object.
• Type refers to the type of variable, such as integer, string, floating point, or Boolean.
• Data types in JavaScript include:
  • Character: any single character or symbol, such as 'x', '@', or 'y'.
  • String: a series or combination of characters, like "somevariable" or "64kgold".
  • Integer: a number of the set Z = {..., -2, -1, 0, 1, 2,...}.
  • Float (or double): any decimal number, like 97.1 or -97.1.
  • Boolean: truth values, which can be either TRUE or FALSE.
  • Function: a set of instructions or arguments.
  • Object: items that exist in the browser that can be manipulated.
  • Array: a type of object that contains a set of values mapped into keys.
  • Undefined: a variable that has not been given a value yet.
  • Null: a variable that has been defined but has been assigned the value of null.

Syntax Guides

• Syntax refers to a set of rules that determines how a specific language will be written and interpreted by the browser.
• JavaScript is case-sensitive.
• JavaScript is processed from top to bottom.
• The syntax for manipulating an object using a method or property is Object.Method() or Object.Property().
• Quotes are used to tell the browser what is to be displayed exactly as it is written in the script.
• Quotes can be single quotes (ʻ) or double quotes (“).
• Comments can be added using “// “ for a single line of comment or by enclosing multiple-line comments between “/* */”.
• The + symbol is used to concatenate a string.
• Statements may contain a semicolon at the end, but it is not necessary in JavaScript unless there are multiple statements in one line.

Variables and Naming Rules

• In JavaScript, variables are containers that contain a value, which can change as required.
• Variables can contain alphanumeric values and the underscore character.
• There should be no spaces in between characters.
• Variables should not have punctuation characters.
• Variables should start with a letter or underscore character.
• Variable names are case-sensitive.

Operators

• An operator is something that takes one or more values to yield another value, making the construct itself an expression.
• An expression is “anything that has a value.”
• Assignment operators are used to both assign and perform math operations.
• Comparison operators are used to compare two values.
• Logical operators are used to make decisions based on one or more truth values (True or False).
• String operators are used to perform simple operations on a string or a piece of text.