Fundamentals but confused

Typically the Debit and credit are accounting terms we have to apply this debit and credit based on the nature of transaction then only we can recognise this is increase this is decrease..

but in secondary stage of accounting ledger posting we have in concept of " TO and By"

everybody telling to means debit by means credit



if I made a deposit to my account rs 18000 means

To Deposit 18000 By


iam I right


tell me how to identify the transaction should disclosure e in ledger posting please give me explanation