Hopefully those of you with cameras have software to adjust your photo resolutions and file sizes, but if you don't try...
There are limits to the size of the photos you can post here. When you go to upload your pictures you will be shown the current specs subject to change.
Photos for use on computer require very low resolution settings unlike printing. It is not unusual to shrink a file 50 times its original size, even more, for use on computer monitor screens.
At Shrink Pictures, a free service, we suggest you choose settings for shrinking to 350 pixels, and GOOD quality, not BETTER or BEST. You are more likely to meet the upload limits here if you do.