[Chemistry4me (OP)]

They are at the bottom of every page:

For example:

 [ Invalid Attachment ]

What do they mean?

[MonikaS]

It tells you how much time the server took to generate the page you're looking at. All the information is stored in a database, which has to be queried to get the information out.

This is basically debugging information, when it takes too long for the server to make the page, you'll have to add more hardware.

[Chemistry4me (OP)]

What is a query?

All the information is stored in a database, which has to be queried to get the information out.

[MonikaS]

A query is a precise request for information from a database.

[Chemistry4me (OP)]

Is it better if you have more or less queries? Or does that have nothing to do with anything?

[MonikaS]

The information has to be retrieved, so the number of queries isn't relevant. The time it took to get the information and generate the page is more important.

[Chemistry4me (OP)]

So does more queries = more information?[][][]

[LeeE]

More queries generally means more different types of information.

This page, that you're looking at now, contains a number of different elements.  For example, at the top right-hand corner will be a little message saying something like:

Hey, [your userID],
you have x messages,
y are new.
2009-01-26, 11:29:17

The number of messages that you have, and the number of those that are unread will be retrieved from the database by a query, or possibly by two separate queries.

Then the body of the page itself contains the posts/responses that people have made in the thread and these responses are also retrieved from the database by a query.  And then, on the left-hand side of each post is some info about the person who made the post, such as their user level and the total number of posts that they have made in the forum, and once again, this information is retrieved by yet further queries.

The actual number of queries required to get all the information displayed on the page will depend on what information is to be displayed how the database holding that information is designed/organised.

[nicephotog]

More queries probably means "more parts of a page" in a page creation context.
Whether it retrieves page capsule parts and data to wrap is irrelevent.
For much its the servers "current(concurrent) process threads"  and "quantity of processing" that will make the major difference.