Each phone has a unique radio module number. For phones that work on the GSM network, this number is called the IMEI, and for phones that work on the CDMA network, this number is called the IMEI. This unique code is given to each phone and can be used for different purposes. For example, to track the phone if it has been stolen or to lock it.
Is there a difference between IMEI and MEID numbers?
No, just IMEI number is used for smartphones with GSM module, and MEID number is used for phones with CDMA module. There is no difference between these two numbers anymore.
To make life easier for people, manufacturers of smartphones, which can work both on GSM and CDMA networks, give them the same IMEI and MEID numbers.
However, not all device manufacturers do this. Some manufacturers use separate numbers.
How to check a MEID number?
No matter what phone you have: iPhone or Android phone, you can find MEID number by calling * # 06 #, the MEID number will be written above or below IMEI number.
Another way to find out the MEID number is to look it up in the settings or on the box. However, I think that the easiest way is of course to just dial the combination from above.