diff --git a/cachematrix.R b/cachematrix.R
index a50be65aa44..b6d82b38586 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -1,15 +1,36 @@
-## Put comments here that give an overall description of what your
-## functions do
-
-## Write a short comment describing this function
-
+# makeCacheMatrix:This function creates a special "matrix" object 
+# that can cache its inverse
 makeCacheMatrix <- function(x = matrix()) {
-
+  iv <- NULL
+  ## Set the value of the matrix
+  set <- function(y) {
+    x <<- y
+    iv <<- NULL
+  }
+  ## Get the value of the matrix
+  get <- function() x
+  ## Set the value of the inverse
+  setiv <- function(inverse) iv <<- inverse
+  ## Get the value of the inverse
+  getiv <- function() iv
+  list(set = set, get = get, setiv = setiv, getiv = getiv)
 }
 
 
-## Write a short comment describing this function
-
+# cacheSolve: This function computes the inverse of the special "matrix" 
+# returned by makeCacheMatrix above
 cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
+  iv <- x$getiv()
+  ## Check if the inverse has already been calculated (and the matrix has not changed)
+  if (!is.null(iv)) {
+    message("getting cached data")
+    ### retrieve the inverse from the cache
+    return(iv)
+  }
+  ## Calculate the inverse 
+  data <- x$get()
+  iv <- solve(data, ...)  
+  # Cache and return the inverse
+  x$setiv(iv)
+  iv
 }