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+# Arrays
+
+## What is an Array?
+- Object used to store a **list** of values
+- All values in array are the **same type**
+    -Eg. int, double, char, string, etc
+
+- Used to store a large number of data
+- Easy to **access** any element in the array
+
+## How to Declare
+- Declaring an array to up to 10 words
+```java
+String array[] = new String[10];
+```
+- Declaring an array and initializing variables at the same time:
+```java
+String array[] = {"s", "d", "f"};
+```
+
+## String Manipulataion
+
+- ```length()` to find the length of a string
+- `stringName.charAt(0)` will output the first character 
+- Each character in a string has a positio. String positions start  at 0
+- `stringName.indexOf("T")` will output the index number that the letter `T` belongs to
+- `stringName.substring(3)` will output all characters after the index #
+- Eg. `string stringName = "Jim hates math"`
+    - Output: `hates math`
+
+- First # is for the index that you want and last number is for the index that you don't wnat
+- `stringName2 = "     i hate math         "`
+- `stringName2.trim(); 
+    - output: i hate math"`
+- `stringName.toLowerCase()` makes every character a lower case letter
+- `stringName.toUpperCase()` makes every character an upper case letter
+
+- concat()
+- `stringname1.concat(stringname2);` will put both string into 1 word
+- `stringname.replce("a", "p");` will replace every `'a'` with `'p'`
+- `stringname1.equals(stringname2);` will return true of false depending on whether the two contain the same value
+- `stringname1.compareTo(stringname2);` is for alphabetical order
+    - if the condition above is < 0, name1 is before name2. >0, name1 is before name2, if =0, its the same string