Added info about the functions in fmt module

Author: shrn01

Diff for: tutorials/learn-golang.org/en/The fmt module.md

@@ -0,0 +1,93 @@
+Tutorial
+--------
+The builtin `fmt` package provides many useful functions which are used to print to console or format to a string. Let's take a look at few of the most used functions.
+
+## fmt.Println()
+
+`fmt.Println()` is the basic print function golang has to offer. It prints the values given to it seperated by commas and adds a newline at the end.
+
+    // fmt.Println() usage
+    fmt.Println("Hello")                            // prints "Hello"
+
+    // multiple arguments of different types can be given seperated by commas
+    fmt.Println("Hello", 22, 98.3, true)            // prints "Hello 22 98.3 true"
+
+    // you can also pass variables as arguments
+    a := "Hello"
+    b := "World"
+
+    fmt.Println(a, b)                               // prints "Hello World"
+
+## fmt.Printf()
+
+`fmt.Printf()` is similar to `printf()` in C language. We give a string with keywords like `%d`, `%v` and give the other arguments which get formatted to these keywords.
+
+    // fmt.Printf() usage
+    fmt.Printf("%s is %d years old.", "Jon Snow", 30)   // prints "Jon Snow is 30 years old."
+
+    // using %v for printing everything
+    fmt.Printf("%v is %v years old.", "Jon Snow", 30)   // prints "Jon Snow is 30 years old."
+
+    // let's try printing type of any variable
+    name := "Jon Snow"
+    fmt.Printf("%T is the type of %v", name, name)      // prints "string is the type of Jon Snow"
+
+Common keywords that are used and what variables are formatted by them
+
+`%d` - integers  
+`%s` - strings  
+`%f` - floating point number  
+`%t` - boolean  
+
+
+`%T` - prints the type of the variable given   
+`%v` - prints any object of any type
+
+
+## fmt.Sprintf()
+
+`fmt.Sprintf()` works just like `fmt.Printf()` but instead of printing to the console it returns the formatted string. It's highly useful for creating formatted strings from variables in golang.
+
+Let's see the function in action.
+
+    // the function returns a formatted string.
+    s := fmt.Sprintf("%s is the son of %s", "Harry", "Lily")  // returns a string "Harry is the son of Lily"
+
+    // let's print the string s
+    fmt.Println(s)                                            // prints "Harry is the son of Lily"
+
+The same keywords that we used for formatting in `fmt.Printf()` apply here too.
+
+Exercise
+--------
+Given two variables, a person's name and his favourite movie, format it and print it to console in the given format. For example the person is `Nolan` and his favourite movie is `Tenet`, your output string should be `Tenet is Nolan's favourite movie`. Use `fmt.Printf()`
+
+Tutorial Code
+-------------
+package main
+
+import "fmt"
+
+func main() {
+    name := "Leonardo"
+    movie := "Lord of the Rings"
+
+    // your code here
+}
+
+Expected Output
+---------------
+Lord of the Rings is Leonardo's favourite movie
+
+Solution
+--------
+package main
+
+import "fmt"
+
+func main() {
+    name := "Leonardo"
+    movie := "Lord of the Rings"
+
+    fmt.Printf("%s is %s's favourite movie", movie, name)
+}

Diff for: tutorials/learn-golang.org/en/Welcome.md

@@ -17,6 +17,7 @@ learn-golang.org is still under construction - If you wish to contribute tutoria
 - [[If-Else]]
 - [[Loops]]
 - [[Functions]]
+- [[The fmt module]]
 
 ### Contributing Tutorials