What is the correct use of SPAM, SAINT, SPAD and SPDD transactions. When should we use each?

What is the correct use of SPAM, SAINT, SPAD and SPDD transactions. When should we use each?

SPAM is for installing support packages, SAINT is used to install new addons. SPAD is for creating printers (I assume you meant SPAU) and SPDD is for adjusting modification to dictionary objects.

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