When I had my first laptop given to me by my fiancé now my husband, he provided me an external hard drive to store our pictures and files. I didn’t look for an external hard drive for myself since I thought that the laptop can be enough for my pictures and or files. But my husband expected enough so he bought one for me. He knows very well that the memory of my laptop alone could not carry all the loads that I’ll be storing.
I was okay with the single 2.5 USB powered drive; this is for no voluminous storage capacity. On the other note if you need it permanently then an external hard drive would be necessary. Mine has the slim one but there are external hard drives that has cooling fan and more bulky this is for large files.