Is it ok to format SD card on computer??

It isn't going to damage the card by formatting it in your computer, but it is always better to format the card using your camera. You can just reformat it again in your camera. It always makes sense to reformat the card everytime you copy all the pictures off of the card and empty it out.

reformatting the cards makes the card readable by the camera. if for some reason you put it in one camera and then took it and put it on another, then the camera would look for its designated folders to save the pictures in to. if it doesnt have it, automatically it adds those folders or in rare circumstances it asks you to format it from the camera. formatting a card from the computer does not damage the card. it is good to format the card after removing pictures once in a while to clear up any possible bits of cache memory stored in the card. like for example you have a 1 GB card but when you look at the camera it says only 900 MB. thats because you might have deleted the pictures but the data is still scatered around the memory. so formatting clears that of. computer to camera and vice versa wont harm your card. what you should not do and NEVER do is to format the card and while it is still formating, take out the card or power the camera/computer off. this will damage the writing/reading capability of the card because it was not able to finish arranging information in it. so dont worry :) u can just format it as many times as you want.

You're fine. It's just that using your camera to format the card will format it in an optimal configuration for your camera and you might be able to put a few more images on the thing. Unless you plan on shooting until your card is full, it shouldn't matter.

Its really depends on your digital camera. Don't worry, you will not damage your card. If you find that the camera will not read/write your card after you format it from you computer, simply format it again using your digital camera. Keep in mind that if you do a full format of your SD card in your computer and later find out there's picture you have not save it yet, it will be impossible for any recovery software to recover the image. Therefore, unless its really necessary, it's always a good idea to format your card using your digital camera only. Unless you know what you are doing.

That should be OK. I have done it many times with several different cameras. However, my Nikon manual does say that formatting on a computer instead of in the camera can cause the camera to write data more slowly to the card. I usually format in camera because it only takes a quick second.