Short answer: no. Longer answer: Yes, but there are some drawbacks.
By and large, burnable media is write once, the end. Any means of circumventing this, short of RW media which can be erased and reburned, will increase the odds that the resulting disc will not be readable on certain systems and/or devices. Including your own if you should use a packet writing program, sometimes referred to as DVD like a floppy programs. Should you ever remove the program used to make these discs, or wipe your computer clean and not install it, try and read the discs on any computer without this program installed, etc... You'll get what looks like a blank disc.
So on the whole, you should burn as many files as you can cram onto a single disc at a time. Then rinse and repeat with all future discs.
I decided to burn some of my pictures on DVD to save some space on my hard drive and I did few discs, but now I wanted to add some more jpg files to the others, but it didn't allow me. Is there a way to add more files to already burned DVD?

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