I've accumulated a lot of photos over the years on my HDD. Most of these are backups from my phone. I have literally 1000's of photos which I don't really want to delete. How can i compress these photos efficiently so they take up as less space as possible. I don't really need the photos but don't want to delete them all either. Is there any application to do this?
Put them all in one folder, right click on the folder, hover over 'send to', and select compressed zipped folder. You can then delete the folder you didn't compress. You can also use something like winrar or 7zip if you want to control how much the folder gets compressed and some other parameters.
Google "file compression software". Many products available: zip format perhaps.
However, it may be safer to just purchase an additional drive or two and back up the photographs as is.
Drives are much cheaper nowadays and a SSD may even be viable for you.
Compressing and uncompressing files is just one more thing to go wrong.
Plug in a "storage" drive (via USB perhaps) and copy the photographs. Use another computer to access the photographs to ensure that they did indeed copy over. Then put the storage drive in a safe place.
Just be aware that no media seems to or will last forever and that eventually the photographics may become unrecoverable for one reason or another.