problems when backup transaction log

I have a problem when backing up the transaction log
the server seems to freeze and other processes on the
server are stopped due to a timeout or locking
my question is what is happening behind when
I backup the transaction log , things that can have an
affect on our other applications run on the same server
10x in advance
ranBOL says:
Transaction Log file is the serial record all transactions that perfomed
against database since since the transaction log was last backed up.With
transaction log backups, you can recover the database to a specific point in
time (for example, prior to entering unwanted data), or to the point of
failure.
Transaction log backup removes all inactive portions of transaction log (
comitted transactions which has written to the disk )
It allows to keep transaction log with acceptable size by resusing its
virtual logs.
"ranm" <ranm@.dec-op.com> wrote in message
news:430f01c3febc$b2be7980$a301280a@.phx.gbl...
> I have a problem when backing up the transaction log
> the server seems to freeze and other processes on the
> server are stopped due to a timeout or locking
> my question is what is happening behind when
> I backup the transaction log , things that can have an
> affect on our other applications run on the same server
> 10x in advance
> ran