Accounting is a process of recording, summarizing, interpreting and communicating financial information in the form of financial statements and management reports.
It is a broad term which encompasses many activities. Making accounting estimates, establishing methods of recording financial data, producing financial reports, analysis of financial reports and communication of financial results are all examples of activities which fall under the umbrella of accounting.
Book-keeping is the input of financial data into the books of an organization. This is usually the starting point for accountants because the data entered by bookkeepers forms the basis of analysis and reporting performed by accountants.
Activities performed by book-keepers are not as complex as the ones performed by accountants, however, being the input for accounting, book-keeping is an important part of the broad accounting process.
Usually book-keeping and accounting activities overlap at times and can be performed by one person, but the two are different in nature and can be differentiated easily.