The colorchecker -- more specifically an XRite passport:
ColorChecker Passport Photo 2 | Request A Quote from X-Rite provides a standard control. You pay about $100.00 for a couple pieces of cardboard with color patches on them in a plastic case. That would seem kind of dumb except that those color patches are created under really tight manufacturing control -- you're paying for that control.
Now you have something in your photo and you know what color it really is. Not only in the sense that you have the physical object but also in the collective sense that your colorchecker patches are the same color as my colorchecker patches. We have a way to work together.
The grey scale or white balance card on the passport can be use to set an accurate white balance in post processing. But beyond that you can use the full color range of the passport to create a camera input profile for the specific lighting condition where you were shooting. That input profile can be applied in ACR (Photoshop) or Lightroom or other processing apps like Capture One or On1 etc. The Passport comes with software to create camera input profiles and software like LR is ready to use the passport to create camera input profiles.
The link above has additional info.