Front Load washers are built with the access door located on the front facing side of your washer. This setup does not require you to lift your clothes up and out. This requires less strain and effort to remove your clothes. These washers require less water during the wash cycle when compared to top load washers.
Top Load washers are built with the access door located on the top face of your washer. There may be certain drawback to this orientation but they are often less expensive.
Portable washers are self contained and are able to be moved into any room with proper plumbing.