1) Learn what you are trying to do
2) Learn about what you are tryting to do it on
3) Check
4) Recheck
5) do it
don't be dumb, November 2014
Ccleaner is very good for elliminating old temporary files forgotten by any application as well as other junk. To be run periodicaly. Every month or two is often sufficient. It makes your system faster by removing file system bloat.
Defragger NEVER EVER delete ANY file. The same hold true fro ALL defragmenters. It makes your system faster by optimising files placement and access.
If you have an SSD drive, you should NOT defragment it. Fragmenting don't affect adversly an SSD performence and defragmenting it can reduce it's life.
Electro, October 2014
A defragger does not delete files - if there are more files each time it's down to natural causes not the defragger.
File fragmentation is where a file is split up and each part put on a different part of the disk - it makes disk operations very inefficient and can slow down the machine.
Defragmentation just tidies things up - brings the fragments together and makes the file whole and in one place.
You might consider some system housekeeping to remove the dross - CCleaner is quite good and it's free.
Wikipedia has a list of Defragmentation Software that you might consider - also an article on defragentation.
