CHANGING WHAT DATA TYPE WILL CAUSE LOSS OF DATA?

Question: CHANGING WHAT DATA TYPE WILL CAUSE LOSS OF DATA?

Answer:    

1. Changing to/from Date & Datetime
2. Changing to Number, Percent and Currency from other data types.
3. Changing from Checkbox, Multiselect picklist, Autonumber to other types.
4. Changing to Multi-select picklist from any type except picklist.
5. Changing to Autonumber except from Text
6. Changing from Text Area (Long) to Email, Phone, Text and URL