diff --git a/cachematrix.R b/cachematrix.R
index a50be65aa44..28553be0b0b 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -1,15 +1,51 @@
-## Put comments here that give an overall description of what your
-## functions do
 
-## Write a short comment describing this function
+## [makeCacheMatrix] is a function that creates a special object, that is
+##  a list of sub-functions (something like Java "methods"):
+## 	- [setMat] set the matrix in the principal function environment;
+##	- [getMat] get the matrix;
+##	- [setInvMat] set the inverse of the matrix in the principal function environment;
+##	- [getInvMat] get the inverse of the matrix.
 
-makeCacheMatrix <- function(x = matrix()) {
 
+makeCacheMatrix <- function(x = matrix()) {
+	inv <- NULL
+	 
+	setMat <- function(y){
+			x <<- y
+			inv <<- NULL
+	}
+	
+	getMat <- function() { x }
+	
+	setInvMat <- function(invmat) { inv <<- invmat }
+	
+	getInvMat <- function() { inv }
+	
+	list(setMat = setMat, getMat = getMat, setInvMat = setInvMat, getInvMat = getInvMat)
 }
 
 
-## Write a short comment describing this function
+## [cacheSolve] is a function that controls if
+## the inverse matrix has already been calculated
+## and stored (returns it with a message), otherwise 
+## it makes the computation at the moment and sets it in the cache. 
+## As you can note, this function call three "methods"
+## created in [makeCacheMatrix].
 
 cacheSolve <- function(x, ...) {
-        ## Return a matrix that is the inverse of 'x'
+	inv <- x$getInvMat()
+	
+	if(!is.null(inv)){
+			message("Inverse Matrix is in the cache!")
+			return(inv)
+	}
+
+	aux <- x$getMat()
+
+	inv <- solve(aux)
+
+	x$setInvMat(inv)
+
+	inv
 }
+