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    DIFFERENT BLOCKS OF BLOCKS EDITOR

                     Built-in blocks are always available and provide basic tools for logic, text, variables
                     and more in the Blocks Editor.

                     1.  Control Blocks: These blocks manage the flow of the program using conditions,

                         loops and event triggers. They help you decide what happens and when. Example:

                             if         Tests a given condition. If the condition is true, it runs the specified
                          then
                                        blocks; if not, it skips them.
                             if
                          then         Tests a given condition. If it is true, the blocks in the then part run;

                          else         if it is false, the blocks in the else part run.

                     2.  Logic Blocks: These blocks allow you to make decisions using true/false values. You

                         can compare values and use logical operations like AND, OR and NOT. Example:

                                   Represents  the  constant  value true.  It is  used  to  set  the  Boolean
                        true
                                   properties of components or assign a condition value to a variable.

                                   Represents  the  constant  value  false. It  is  used  to  set  the  Boolean
                        false
                                   properties of components or assign a variable to represent a condition.

                     3.   Math Blocks: These blocks perform basic and advanced mathematical calculations.

                         You can add, subtract, multiply, divide and more. Example:

                                         This block lets you display numbers in decimal form and can also
                        decimal   0
                                         show them in other formats, such as binary or hexadecimal.

                                         This block compares two values to check if one is greater than,
                             =
                                         less than or equal to the other.

                     4.   Text Blocks: These blocks are used to work with words and characters. You can

                         join, split, change and compare text. Example:

                                        This string can contain any characters (letters, numbers or other
                                        special characters). On App Inventor it will be considered a Text object.

                              join      Appends all of the inputs to make a single string. If there are no
                                        inputs, it returns an empty string.

                                                                                    Creating Apps with MIT App Inventor  101

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