what do you understand by the …

Bookkeeping means recording all business transactions (e.g., sales, purchases, payments, etc.) in the books of prime entry. It is similar to journaling when you record everything that happened throughout the day, but in a predefined format. While these records are essential for producing financial statements, this part of work is mostly routine and is first to be automated in the accounting department.
Accounting is a broader term, it includes bookkeeping and reporting. Reporting is a more complex process involving analysing, interpreting and summarising financial data and presenting the results in the form of a report. The outcome is either financial statements for financial reporting or management reports for management reporting.
Accountancy usually relates to a professional practice, i.e. a consultancy providing accounting services, or the profession itself.