Difference between savepiplelinetofile & savepipline?

pub.flow:savePipelineToFile - WmPublic. Saves the current pipeline to a file on the machine running webMethods Integration Server.This service is helpful in the interactive development or debugging of an application. In some cases, however, using the Pipeline debug property for the debugging of an application is more efficient.

pub.flow:savePipeline - WmPublic. Saves a pipeline into memory, for later retrieval with pub.flow:restorePipeline.After a successful invocation of savePipeline, a snapshot of pipeline fields will be saved in

memory under the key provided by $name. Note that because the pipeline is saved to memory, it will not be available after a server restart. This service is helpful in the interactive development or debugging of an application