diff --git a/.DS_Store b/.DS_Store
new file mode 100644
index 00000000..2b2567e9
Binary files /dev/null and b/.DS_Store differ
diff --git a/lib/00_hello.rb b/lib/00_hello.rb
index a5fd1d52..17341fa5 100644
--- a/lib/00_hello.rb
+++ b/lib/00_hello.rb
@@ -1,7 +1,10 @@
 def hello
-
+  return "Hello!"
 end
 
 def greet(name)
-
+  return "Hello, #{name}!"
 end
+
+
+
diff --git a/lib/01_temperature.rb b/lib/01_temperature.rb
new file mode 100644
index 00000000..328a7985
--- /dev/null
+++ b/lib/01_temperature.rb
@@ -0,0 +1,8 @@
+def ftoc(temperature)
+  return ((temperature-32)/1.8).round(1)
+end
+
+def ctof(temperature)
+  return (temperature*1.8+32).round(1) 
+end
+
diff --git a/lib/02_calculator.rb b/lib/02_calculator.rb
new file mode 100644
index 00000000..539a593d
--- /dev/null
+++ b/lib/02_calculator.rb
@@ -0,0 +1,32 @@
+def add(a,b)
+  return a + b
+end
+
+def subtract(a,b)
+  return a - b
+end
+
+def sum(a)
+  return a.inject(0, :+)
+end
+
+def multiply(a,b)
+  a = a.to_i
+  b = b.to_i
+  return a*b
+end
+
+def power(a,b)
+  return a**b
+end
+
+def factorial(a)
+  b = 1
+  while a > 0
+    b = b * a
+    a = a-1
+  end
+  return b
+end
+    
+  
\ No newline at end of file
diff --git a/lib/03_basics.rb b/lib/03_basics.rb
new file mode 100644
index 00000000..15a7bdea
--- /dev/null
+++ b/lib/03_basics.rb
@@ -0,0 +1,23 @@
+def who_is_bigger(a,b,c)
+  
+  if a == nil || b == nil || c == nil #gestion d'un nil, en a, b ou c
+    return "nil detected"
+  else
+    hash = {a:a, b:b, c:c} #création d'un hash pur associer une clé a,b,c pour chaque valeur de a, b et c
+    return "#{hash.key(hash.values.max)} is bigger" #la key de la valeur max
+  end
+end
+
+def reverse_upcase_noLTA(word)
+  word.upcase.reverse.delete"ALT"
+end
+
+def array_42(*array)
+  array = array.to_s #conversion en string pour permettre la bonne execution de la fonction .include
+  return array.include? "42"
+end
+
+def magic_array (*array)
+  return array.flatten.sort.map{|x| x*2}.delete_if{|x| x%3 == 0}.uniq
+end
+
diff --git a/lib/04_simon_says.rb b/lib/04_simon_says.rb
new file mode 100644
index 00000000..d4e38fe6
--- /dev/null
+++ b/lib/04_simon_says.rb
@@ -0,0 +1,24 @@
+def echo(word)
+  return word
+end
+
+def shout(word)
+  return word.upcase
+end
+
+def repeat(word, b=2)
+  return ((word + " ") * b).strip
+end
+
+def start_of_word (word, b = 1)
+  return word [0, b]
+end
+
+def first_word(word)
+  return word.split(' ').first
+end
+
+def titleize(word)
+  return 
+end
+puts titleize("hello you")
\ No newline at end of file
diff --git a/lib/05_timer.rb b/lib/05_timer.rb
new file mode 100644
index 00000000..e69de29b
diff --git a/lib/06_pig_latin.rb b/lib/06_pig_latin.rb
new file mode 100644
index 00000000..e69de29b
diff --git a/spec/02_calculator_spec.rb b/spec/02_calculator_spec.rb
index 08ed2d7f..8c3309c0 100644
--- a/spec/02_calculator_spec.rb
+++ b/spec/02_calculator_spec.rb
@@ -47,23 +47,39 @@
     expect(multiply(3, 4)).to eq(12)
   end
 
-  it "multiplies two other numbers"
+  it "multiplies two other numbers" do
+    expect(multiply(2, 2)).to eq(4)
+  end
     # one other test here, don't forget do end ;)
 
-  it "multiplies two other numbers, one of them being 0"
+  it "multiplies two other numbers, one of them being 0" do
+    expect(multiply(2, 0)).to eq(0)
     # one last test, with 0 in it
-
+  end
 end
 
 describe "#power" do
-  it "raises one number to the power of another number"
+  it "raises one number to the power of another number" do
+    expect(power(2,2)).to eq(4)
+  end
 end
 
+
 # http://en.wikipedia.org/wiki/Factorial
 describe "#factorial" do
-  it "computes the factorial of 0"
-  it "computes the factorial of 1"
-  it "computes the factorial of 2"
-  it "computes the factorial of 5"
-  it "computes the factorial of 10"
+  it "computes the factorial of 0"do
+    expect(factorial(0)).to eq(1)
+  end
+  it "computes the factorial of 1" do
+    expect(factorial(1)).to eq(1)
+  end
+  it "computes the factorial of 2"do
+    expect(factorial(2)).to eq(2)
+  end
+  it "computes the factorial of 5" do
+    expect(factorial(5)).to eq(120)
+  end
+  it "computes the factorial of 10" do
+    expect(factorial(10)).to eq(3628800)
+  end
 end