Manual Welding Process: Electrode travel as well as Welding Holder travel both are controlled Manually. Example Arc welding.
Semi-automatic welding: Electride travel is automatic(spool feed), where as the welding holder travel is manual. Ex: MIG and TIG welding.
Automatic welding: Both electrode travel(spool feed) and holder travel is automatic. Example: submerged Arc Welding, ENC welding etc.