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landing/docs/.Bash-Scripting/008-bash-arrays.md

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+# Bash Arrays
+
+If you have ever done any programming, you are probably already familiar with arrays. 
+
+But just in case you are not a developer, the main thing that you need to know is that unlike variables, arrays can hold several values under one name.
+
+You can initialize an array by assigning values divided by space and enclosed in `()`. Example:
+
+```bash
+my_array=("value 1" "value 2" "value 3" "value 4")
+```
+
+To access the elements in the array, you need to reference them by their numeric index.
+
+>{notice} keep in mind that you need to use curly brackets.
+
+* Access a single element, this would output: `value 2`
+
+```bash
+echo ${my_array[1]}
+```
+
+* This would return the last element: `value 4`
+
+```bash
+echo ${my_array[-1]}
+```
+
+* As with command line arguments using `@` will return all arguments in the array, as follows: `value 1 value 2 value 3 value 4`
+
+```bash
+echo ${my_array[@]}
+```
+
+* Prepending the array with a hash sign (`#`) would output the total number of elements in the array, in our case it is `4`:
+
+```bash
+echo ${#my_array[@]}
+```
+
+Make sure to test this and practice it at your end with different values.
+
+## Substring in Bash :: Slicing
+
+Let's review the following example of slicing in a string in Bash:
+
+```bash
+#!/bin/bash
+
+letters=( "A""B""C""D""E" ) 
+echo ${letters[@]}
+```
+
+This command will print all the elements of an array.
+
+Output:
+
+```bash
+$ ABCDE
+```
+
+
+Let's see a few more examples:
+
+- Example 1  
+
+```bash
+#!/bin/bash
+
+letters=( "A""B""C""D""E" ) 
+b=${letters:0:2}
+echo "${b}"
+```
+
+This command will print array from starting index 0 to 2 where 2 is exclusive.
+
+```bash
+$ AB
+```
+ 
+ - Example 2
+
+```bash
+#!/bin/bash
+
+letters=( "A""B""C""D""E" ) 
+b=${letters::5}
+echo "${b}"
+```
+
+This command will print from base index 0 to 5, where 5 is exclusive and starting index is default set to 0 .
+
+```bash
+$ ABCDE
+```
+
+- Example 3
+
+```bash
+#!/bin/bash
+
+letters=( "A""B""C""D""E" ) 
+b=${letters:3}
+echo "${b}"
+```
+
+This command will print from starting index
+ 3 to end of array inclusive .
+
+ ```bash
+ $ DE
+ ```