Alot of people already know this but if you don’t you can spare alot of time with tedious images tasks by using the ‘Action’ tool.
I often resize 20 or 30 images together and it doesnt really make much sense to do them one by one. The tool is fairly intuitive to use.
First click on the windows tab, click on actions to ensure the actions window appears on the screen. Then click on the create new icon. When ready to go press the record button and dont forget to stop it.
When you are ready to reuse later, just click on file and batch. Put in the source and target destination folders and select your Action.
Ready to go, hope it saves you some time.