can someone explain the concept of "strings (or whatever) being immutable"

[Cameron Simpson]

On 02Jun2014 21:06, Deb Wyatt <codemonkey at inbox.com> wrote:
>> Deb Wyatt <codemonkey at inbox.com> writes:
>>> [no text]
>>
>> Deb, can you expand a bit – and write the question in the body of your
>> message? It's not clear what you want explained.
[...]
>that's strange that you see no text.  The body of my email was as follows:
>"""a_string = "This is a string"
[... etc ...]

That is because whatever you're using for email sent both HTML and plain text, 
but in complete violation of sanity, left the plain text version empty. Ben's 
mailer is showing him the plain text version, which is perfectly reasonable, 
and why he saw nothing.

Please adjust your mailer to send plain text only. It is all you need anyway, 
and renders more reliably for other people.

Thank you,
Cameron Simpson <cs at zip.com.au>