[Pharo-users] Transcript: printString or asString

Hi folks. I'm starting in Pharo studies by FUN Mooc. In Week 03, on An Overview of Essential Collections there is the example below: | days | days := Dictionary new. days at: #January put: 31; at: #February put: 28; at: #March put: 31. days keysAndValuesDo: [ :k :v | Transcript show: k asString, ' has ', v printString, ' days' ; cr ] The code in blue I change for days keysAndValuesDo: [ :k :v | Transcript show: k asString, ' has ', v asString, ' days' ; cr ] And works too on Playground. There is something different about both? There is someone better than other? Thanks in advance, Samuel T. Santos