There are lots of articles online explaining in detail how IMEI's work and are constructed, but for this article we are providing a basic definition.
IMEI or International Mobile Equipment Identity is a number that allows a mobile phone network / carrier to identify your phone.
Sometimes on a device it may not display an IMEI OR it may show IMEI/MEID. MEID stands for Mobile Equipment Identifier. Whilst they are different, for the most part, the two can be regarded as the same thing.
If your device has two physical SIM cards or a physical and an embedded eSIM it is common to see IMEI2 / IMEI 2 / IMEI#2 listed. This allows the mobile phone network / carrier to identify your device and link it to your second connection (phone number) if enabled.
How to Find your Device IMEI / MEID / IMEI 2
Check your device packaging, it will usually be found near the barcode. It may also be printed physically on the back of your device or under the battery.
However our recommended way is to check within the phone itself, refer here for Instructions based on your operating system.