The document describes various BPEL activities including: - The Assign activity is used for data manipulation like copying data. - The Assert activity enables assertions to be performed on expressions. - The Compensate activity invokes compensation on an inner scope that has completed successfully. - The Invoke activity specifies an operation to invoke on a partner service. It can invoke synchronous or asynchronous web services. - The Pick activity waits for one event from a set of events to occur and performs the associated activity.