Dug a hole for myself when a youngster asked me about web browsers, HTTP
etc.

Thought I was being clever when I told him that a browser was a search
engine that allowed you to view copies of web pages stored on web servers.

He then said that if you can only view web pages, how come you have the
option to download programs on certain sites?

Eh?

Before I dig a deeper hole for myself, am I right in thinking that when you
request to "download", the site switches you to its FTP Server and that most
browsers will allow you to download from it?

On Sun, 4 Oct 2009 08:18:54 +0100, Smirnoff wrote:

> Dug a hole for myself when a youngster asked me about web browsers, HTTP
> etc.
>
> Thought I was being clever when I told him that a browser was a search
> engine that allowed you to view copies of web pages stored on web servers.
>
> He then said that if you can only view web pages, how come you have the
> option to download programs on certain sites?
>
> Eh?
>
> Before I dig a deeper hole for myself, am I right in thinking that when you
> request to "download", the site switches you to its FTP Server and that most
> browsers will allow you to download from it?

A browser is not a search engine. It is an HTTP client, used to access
content on an HTTP server. And a browser can download any content using
HTTP, including files. Whether the browser uses HTTP, or FTP to download a
file depends upon how the file server is configured.

The web browser is the engine for display of certain data. HTTP just defines
the coded commands used to download that data, and how the client will
display that data.

--
Norman
~Oh Lord, why have you come
~To Konnyu, with the Lion and the Drum

"Smirnoff" <someone@nospam.invalid> wrote in message
news:#7OpzLMRKHA.4580@TK2MSFTNGP06.phx.gbl...
> Dug a hole for myself when a youngster asked me about web browsers, HTTP
> etc.
>
> Thought I was being clever when I told him that a browser was a search
> engine that allowed you to view copies of web pages stored on web servers.
>
> He then said that if you can only view web pages, how come you have the
> option to download programs on certain sites?
>
> Eh?
>
> Before I dig a deeper hole for myself, am I right in thinking that when
> you request to "download", the site switches you to its FTP Server and
> that most browsers will allow you to download from it?

Sorry to reply to my own post but suspect I did not explain myself properly,
hence the deafening silence.

When I stated in my original post that browsers allowed you to view web
pages, obviously this also includes the ability to click on links to view
other pages. My understanding is that this transfers a copy of the web page
to the browser but it is not kept in memory, merely saved as a temp internet
file. All of this is done using HTTP.

What I'm trying to establish is: Can files/programs only be downloaded via a
browser?

i.e. When clicking on a "Download" link, presumably this has to be via an
FTP Server. Is the file downloaded via the browser or does it merely
"request" the file from the site's FTP Server?

"Smirnoff" <someone@nospam.invalid> wrote in message
news:uR#6#HZRKHA.4692@TK2MSFTNGP06.phx.gbl...
>
> "Smirnoff" <someone@nospam.invalid> wrote in message
> news:#7OpzLMRKHA.4580@TK2MSFTNGP06.phx.gbl...
>> Dug a hole for myself when a youngster asked me about web browsers, HTTP
>> etc.
>>
>> Thought I was being clever when I told him that a browser was a search
>> engine that allowed you to view copies of web pages stored on web
>> servers.
>>
>> He then said that if you can only view web pages, how come you have the
>> option to download programs on certain sites?
>>
>> Eh?
>>
>> Before I dig a deeper hole for myself, am I right in thinking that when
>> you request to "download", the site switches you to its FTP Server and
>> that most browsers will allow you to download from it?
>
> Sorry to reply to my own post but suspect I did not explain myself
> properly, hence the deafening silence.
>
> When I stated in my original post that browsers allowed you to view web
> pages, obviously this also includes the ability to click on links to view
> other pages. My understanding is that this transfers a copy of the web
> page to the browser but it is not kept in memory, merely saved as a temp
> internet file. All of this is done using HTTP.
>
> What I'm trying to establish is: Can files/programs only be downloaded via
> a browser?
>
> i.e. When clicking on a "Download" link, presumably this has to be via an
> FTP Server. Is the file downloaded via the browser or does it merely
> "request" the file from the site's FTP Server?

No, your understanding is entirely wrong.

FTP and HTTP are 2 protocols for transferring data from a "server" to a
"client". FTP is traditionally used to provide file transfer capabilities,
but it certainly isn't a requirement for transferring files. I have many
websites where I allow users to downloads files (such as ZIP archives, PDF
documents, etc) from a HTTP server.

You don't even need a web browser to "download" web pages - I regularly use
a telnet client to do so for debugging applications.

--
Dan

On 10/05/2009 02:00 AM, Smirnoff wrote:
>
> "Smirnoff" <someone@nospam.invalid> wrote in message
> news:#7OpzLMRKHA.4580@TK2MSFTNGP06.phx.gbl...
>> Dug a hole for myself when a youngster asked me about web browsers, HTTP
>> etc.
>>
>> Thought I was being clever when I told him that a browser was a search
>> engine that allowed you to view copies of web pages stored on web servers.
>>
>> He then said that if you can only view web pages, how come you have the
>> option to download programs on certain sites?
>>
>> Eh?
>>
>> Before I dig a deeper hole for myself, am I right in thinking that when
>> you request to "download", the site switches you to its FTP Server and
>> that most browsers will allow you to download from it?
>
> Sorry to reply to my own post but suspect I did not explain myself properly,
> hence the deafening silence.
>
> When I stated in my original post that browsers allowed you to view web
> pages, obviously this also includes the ability to click on links to view
> other pages. My understanding is that this transfers a copy of the web page
> to the browser but it is not kept in memory, merely saved as a temp internet
> file. All of this is done using HTTP.
>
> What I'm trying to establish is: Can files/programs only be downloaded via a
> browser?
>
> i.e. When clicking on a "Download" link, presumably this has to be via an
> FTP Server. Is the file downloaded via the browser or does it merely
> "request" the file from the site's FTP Server?

[Disclaimer -- the following is vastly oversimplified!]

Whenever you click on a link, you are "downloading" a
"file" (i.e. receiving a bunch of data from the server).
Your browser decides what to do with the "file" based
on what kind of file it thinks it is getting.

If the file is html (contains text written in the html
"language"), the browser will display it as a web page.
If the file is an audio or video file, it will play it.
If the file something that should be saved, the browser
will pop up a "Save as" dialog and copy the received data
to the file you specify.

*How* it gets the file is determined by the beginning
part of the the link which says what protocol the server
uses to provide the file. If the link starts with "http://"
the browser will know it has to send http commands to the
server to get the file. If the link starts with "ftp://"
the browser will have to use ftp commands to get the file.
(The ftp protocol existed long before the http and the web
did.)

However in both the http and and ftp cases, the browser
is downloading the file and what it does with the file
(display as a web page, play it, save it, etc) depends
on what kind of file the browser thinks it is.

An illustrative example is to go to an ftp site, for
example,
ftp://ftp.monash.edu.au/pub/nihongo
In the list of files, click on "00INDEX.html" (the first
one). Note that it displays as a normal web page, even
though you received it using the ftp protocol (as you can
see by the "ftp://" prefix in your browser's address bar.)

HTH