Difference between Data "Import and Export" and "Restore from backup"

Hi All,

Could some help us understand the difference between the impact of using Import and Export functionality and Restore from backup in terms of migrating data to a different application <g class="gr_ gr_273 gr-alert gr_gramm gr_run_anim Punctuation multiReplace" data-gr-id="273" id="273">environment.</g> 

We wanted to understand the impact in terms of Memory, CPU utilisation and does any of these processes uses the concept of locks? 

We have seen some issue with production application when tried to migrate data with "Import and Export" wizard.

Regards,

Krishna.