What is "header" means in "Copy and paste" Excel?

Excel Header 

1. When importing the attendees, there's the first row, which will set as the header.

Therefore, be aware the wording of the first row when you are importing the attendees' details from Excel.

Remarks: 

1. Column name cannot be blank
2. Total number of rows must be less than or equal to 10000.
3. Special characters are not supported in headers. Please make sure to put alphabetic and/ or numeric characters only.

2. This is the first row in the excel and it will be the header when importing the data.  Column name cannot be blank