Deleting a column in a pandas frame
With reading a csv file and loading its content in a dataframe, you create a python object called df.
Then, with the three methods you showed us, you only delete some content of this object, not the csv's content.
I would recommend you to use the first method, del, keep working with the dataframe and not reading the csv again.
Let me know if anything is unclear, please.
I have been trying the past 40 minutes to delete a specific column (Name) from my data frame but no method seems to work. I am using jupyter notebook by the way, not sure if that may be an issue. I am also 100% sure that the column name is named Name and that it is not the index of the data frame -- I am using the Titanic data set. 

What I have tried:

del df['Name']
df.drop('Name', axis=1, inplace=True)
df = df.drop('Name', 1)

All the above seem to delete the column, but when re-reading the csv the column appears back. Any clue on why this is happening?