Add new file

Grade 10/Computer Science/ICS4U1/Methods.md

@@ -0,0 +1,71 @@
+# Methods
+
+## What are methods
+
+A java method can be interpreted as a subprogram. It is a collection of statements taht are grouped togehter to perform an operation
+
+## Built- in vs User-defined Methods
+
+Built-in:
+BUild-i nmethods arep art of hte complier package such as system.out.println
+
+Function (return) - Type: it calcualtes and return a value
+```java
+public static int claculate(int number){
+```
+
+procedure-type: executes some commands
+
+Function (return)- type: 
+pubic static return type method name (parameter 1)
+
+procedure-type method:
+public static void method-name (paramenter 1)
+
+## How to create a method
+
+In general, method declarations has 5 basic components (figure 2.):
+- **Modifier:** defines access type of the method i.e. from were it can be accessed in your application (For example: public)
+- **The return type:** the data type of the value returned by the method or void if it does not return a value (procedure and function type)
+- **Method name:** a specific names that identifies the method that  can be used to invoke it later
+- **Parameter list:** Comma separated list of the input parameter are defined preceded with their data type, within the enclosed parentheses, If there are no parameters, you must use empty parenteses()
+
+## Method declaration
+- **Method body:** It is enclosed between braces. the code that you need to be execute to perfrom your intended operations
+
+```java
+public int max(int x, int y) {
+
+```
+
+## How to call a method (method invocation
+
+To invoke a method you need the method name with the parameter list defined between parentheses
+
+Exammple:
+Method Name (paramter list)
+
+Must have () parentheses when calling a method, even with no passing parameters
+
+## Pass-By-Value
+**What happens:** When a method is called ,a copy of the value of each argument is passed  to the method
+
+**In the second method:** This copy can be changed inside the method, however such a change has no effect on the actual argumnet
+
+```
+int num=10;
+double decimal = 5.2;
+NumberManeuvers(num decimal);
+System.out.println("num = " + num + "and decimal = " + decimal);
+
+public static void numberManeuvers(int i, double j) {
+    if(i == 10) {
+        j = 6.2;
+        i = 12;
+    }
+}
+// output = num = 10 and decimal = 5.2
+```
+
+## Pass-By-Reference
+