A template is the label/card stock you are using. This might be Avery 5160 for address labels, Gaylord 47-284 for spine labels or Avery 28371 for your patron cards, just to give a couple of examples. These labels will include all of the information you will need for setting up a Koha, this information may be on the packaging, and if not it can usually be found on the vendor's website.
A profile is a set of “adjustments” applied to a given template just prior to printing which compensates for anomalies unique and peculiar to a given printer (to which the profile is assigned). This means if you set a template up and then print a sample set of data and find that the items are not all aligned the same on each label, you need to set up a profile for each printer to make up for the differences in printing styles, such as the shifting of text to the left, right, top or bottom.
If your cards are printing just the way you want, you will not need a profile.
A layout defines the text and images that will be printed on to the card and where it will appear.
A batch is a collection of patrons for whom you want to generate cards.
Images uploaded using this tool will appear on the menu when creating patron card layouts. You are limited in how many images you can upload (not counting patron images) by the ImageLimit system preference.
IMPORTANT: Images must be under 500k in size.
TIP: Pictures uploaded with this tool should be at least 300dpi which is the minimum quality for a printable image.