lesson_01.ipynb

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    "# Beginner Bootstrap Lesson 1: Basic types, collections, and flow control\n",
    "\n",
    "## `Hello, world!`\n",
    "\n",
    "For some reason, the first program people write when learning a new programming language displays _Hello, world!_ on the screen. If you are curious as to why this is so, I'm sure you could learn the reasons with a well-formed _Google_ search. In Python, this program at it's most basic would look like this:"
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      "Hello, world!\n"
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    "#!/usr/bin/env python3\n",
    "\"\"\"A program to print 'Hello, world!'\"\"\"\n",
    "print(\"Hello, world!\")"
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   "source": [
    "## Strings\n",
    "\n",
    "In Python, sometimes we want to store a word (or words) to be used again and again in our programs. Python calls these _strings_. So, we could rewrite our _Hello, world!_ program like this:"
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      "Hello, world!\n",
      "Goodbye, world!\n"
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    "#!/usr/bin/env python3\n",
    "\"\"\"A program to print 'Hello, world!'\"\"\"\n",
    "message = \"Hello, world!\"  # message is a string\n",
    "print(message)\n",
    "\n",
    "message = \"Goodbye, world!\"  # the string message refers to changes here\n",
    "print(message)"
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    "### Variables\n",
    "\n",
    "In the second version of our _Hello, world!_ program, we added a _variable_ called `message`. A _variable_ is a name that refers to an _object_. In this example, the _object_ is the _string_ `\"Hello, world!\"`. Later in the program, the _object_ referred to by `message` is changed to `\"Goodbye, world!\"`."
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