There are two main camera photo formats: RAW and JPEG. Which format would be better? The answer to this question mostly depends on what your goals are for your photos. First, it's important to understand the differences between the two formats.
RAW is the absolute raw data recorded by your camera's sensor. As a result, it's important to understand that raw is not an output format. Simply speaking, a "raw" file is an unfinished photo. In fact, it's technically not even a photo at all, even though it can be read as one by the right software. Raw files are intended to provide extremely detailed information about an image so that they can be processed into a final photo meant for output and consumption (such as JPEG or TIFF). A raw file requires processing of some level to be converted into a usable digital photo.
JPEG is a standard that has been around since the early 1990s. Because of a JPEG's ability to compress extremely well while maintaining image quality, it quickly became the standard for displaying photos on the internet - which in turn became the standard for compressed images generated by digital cameras. JPEG is "lossy" compression, which means the more an image is compressed (making the file sizes smaller), the less quality and detail is retained. Digital cameras typically offer several quality levels which balance file size against quality.
Advantages of RAW Raw files contain the maximum amount of image data that can be generated by your camera. That means you get the highest possible resolution with the maximum level of color data your camera is capable of recording.
Since raw files contain the raw data recorded by the camera's sensor, you have extraordinary latitude in editing your photos. You are generally able to recover details from extreme highlights or deeply underexposed areas that would be otherwise impossible to recover in a JPEG.
Raw files can have their white balance adjusted during post-processing. Since white balance settings on a camera have no bearing on the visible information in a raw image file, you can completely adjust the white balance as appropriate during raw processing.
Raw files enjoy non-destructive editing. When you process a raw file and make changes to the appearance of the resulting photo, you are not actually changing the original sensor data at all. That means if you process a photo and export it as a JPEG, you can come back to the photo a year later, wipe out all of your adjustments, and re-edit the image starting fresh from the original raw data.
Disadvantages of RAW As mentioned earlier, raw files require processing to be turned into a usable photo. That means you're going to have to spend at least a little time importing/exporting your images using raw processing software before being able to share or print them. And since unprocessed raw images will always look more flat and bland than their processed counterparts, it often takes significant processing work to get them looking good.
Raw files are (typically) huge. Since raw files contain the maximum amount of uncompressed sensor data capable of being recorded by your camera, they are several orders of magnitude larger than their JPEG counterparts. That means shooting raw will use significantly more space on your memory card than shooting JPEG.
Writing raw is slower. You generally have slower performance (especially in burst mode) shooting raw than you would shooting JPEG. The amount of time it takes a camera to write raw sensor data to a memory card is significantly longer than processing a JPEG and writing the much smaller file to the memory card.
Advantages of JPEG No post-processing needed. Since your camera handles everything from post-processing to applying white balance to compressing, shooting JPEG means you have a much faster workflow from firing the shutter to having a usable photo. JPEG files are essentially "ready to eat." Take them out of the package (memory card) and you have a fully-baked image ready to share or print.
Writing JPEG is faster. You generally have faster performance (especially in burst mode) shooting JPEG than you would shooting raw. The amount of time it takes a camera to write JPEG sensor data to a memory card is significantly faster than taking the raw sensor data, creating an embedded JPEG preview, and writing the much larger file to the memory card.
You can fit more JPEG on a memory card than raw files. Since JPEG images are compressed, they take significantly less space than their raw data counterparts.
Disadvantages of JPEG Since JPEG is "lossy" compression, you lose massive amounts of image information when shooting JPEG. You will end up with an image that contains the same number of pixels, but many of those pixels will have been created by the JPEG compression algorithm "guessing" what those pixels should look like.
Post-processing becomes significantly more difficult. Since you are dealing with compressed data, much of the information in over or under-exposed areas of an image will be permanently lost and impossible to recover. Image quality as a whole suffers, and operations like sharpening and noise reduction become far more destructive and often amplify the appearance of undesirable artifacts in the image rather than the intended effect of making an image look more clean.
The white balance settings set in the camera will be permanently applied to the image, making white balance corrections significantly more difficult, and in some cases impossible.
JPEG editing is destructive. This means that editing a JPEG file runs the risk of overwriting your original image data, especially if you use a program such as Photoshop or GIMP to process your JPEG files. Additionally, each time a JPEG file is opened, edited, and saved, it loses quality each time.
The question of "which format should I use" again comes back to the goals for your photos. If you are happy with the JPEG images created by your camera and want to spend minimal time adjusting the images after the fact, shoot JPEG. If you intend to process your images beyond what your camera can do and need the maximum amount of image data available to you, shoot RAW.
