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    "# Chained Comparison Operators\n",
    "\n",
    "An interesting feature of Python is the ability to *chain* multiple comparisons to perform a more complex test. You can use these chained comparisons as a shorthand for larger Boolean Expressions.\n",
    "\n",
    "In this lecture we will learn how to chain comparison operators and we will also introduce two other important statements in python: **and** and **or**.\n",
    "\n",
    "Let's look at a few examples of using chains:"
   ]
  },
  {
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   "execution_count": 1,
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      "text/plain": [
       "True"
      ]
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     "execution_count": 1,
     "metadata": {},
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   "source": [
    "1 < 2 < 3"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "The above statement check if 1 was less than 2 **and** if 2 was less than 3. We could have written this using an **and** statement in Python:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "1<2 and 2<3"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "The **and** is used to make sure two checks have to be true in order for the total check to be true. Let's see another example:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "1 < 3 > 2"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "The above checks if 3 is larger than both the other numbers, so you could use **and** to rewrite it as:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "1<3 and 3>2"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Its important to note that Python is checking both instances of the comparisons. We can also use **or** to write comparisons in Python. For example:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "1==2 or 2<3"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Note how it was true, this is because with the **or** operator, we only need one *or* the other two be true. Let's see one more example to drive this home:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "1==1 or 100==1"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Great! For an overview of this quick lesson: You should have a comfortable understanding of using **and** and **or** statements as well as reading chained comparison code.\n",
    "\n",
    "Go ahead and go to the quiz for this section to check your understanding!"
   ]
  }
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