Question

what is the difference between field validation rule and record validation rule?

Answer 1

Field Validation is clean useful computer data and Record Validation is compares the values of two or more fields.

Answer 2

Field level controls how the data can be enter in a database field.  

Record level controls how the data can be enter in a record or row of data in a database table....  

example: suppose you have a field called 'student_phone_number'

then the validation rule wud be 'only 10 digits allowed.' this will be valid for all entries in this field.

if you have a field called 'marks'

then the record validation rule wud be 'less than 100 & more than -1'.