title: pandas series inside pandas data frame
body: <p>I have imported data from a database in my Jupyter notebook.</p>
  
  <pre><code>import pyodbc
  cnxn = pyodbc.connect('...')
  cursor =cnxn.cursor()
  cursor.execute("...")
  tables = cursor.fetchall()
  </code></pre>
  
  <p>And then I convert <code>tables</code> into a <code>data frame</code>.</p>
  
  <pre><code>Db2Df = []
  
  for row in tables:
      Db2Df.append({...,...})
  
  df = pd.DataFrame(Db2Df)
  df.head()
  </code></pre>
  
  <p>So after doing the above, I am exploring my data.</p>
  
  <p>Input:</p>
  
  <pre><code>type(df)
  type(df["Column_1"])
  type(df["Column_1"][0])
  </code></pre>
  
  <p>Output: </p>
  
  <pre><code>pandas.core.frame.DataFrame
  pandas.core.series.Series
  str
  </code></pre>
  
  <p>My question is, why is the data type like that (why does it do that)? A <code>str</code> inside a <code>pandas series</code> inside a <code>data frame</code>? And when working with the data, should I be considering using the <code>data frame</code> or <code>series</code>, if I want to manipulate the <code>str</code>...</p>
  
  <p>Thank you.</p>