Placements confusion - help? One widget affecting another widget

[aboweFIS]

I've made a couple of footer widgets with HTML fields and when I put them on the same page to work on the Placements, I realized that the tabs on one widget are affecting the other widget. (Clicking the tabs on one widget will trigger tabs on the second widget and cause the display to get all wonky.)

I don't thoroughly understand what I am doing, so I wondered if anyone could point out my error(s)?
*Note I am doing this through the UI.

Visual of Footer4Col:

( Footer3Col is identical, just with 3 cols!)

Here's the json - it's identical for both except for the differentiators, which is what I thought STOPPED one from affecting another?

"HtmlField_Edit": [
  {
    "place": "Content:0#Column 1;0",
    "differentiator": "Footer4Col-Column1"
  },
  {
    "place": "Content:0#Column 2;1",
    "differentiator": "Footer4Col-Column2"
  },
  {
    "place": "Content:0#Column 3;2",
    "differentiator": "Footer4Col-Column3"
  },
  {
    "place": "Content:0#Column 4;3",
    "differentiator": "Footer4Col-Column4"
  },
  {
    "place": "Content:0#Optional;4|Top Row",
    "differentiator": "Footer4Col-TopRow"
  },
  {
    "place": "Content:1#Optional|Copyright",
    "differentiator": "Footer4Col-Copyright"
  },
  {
    "place": "Content:0#Column 1;0",
    "differentiator": "Footer3Col-Column1"
  },
  {
    "place": "Content:0#Column 2;1",
    "differentiator": "Footer3Col-Column2"
  },
  {
    "place": "Content:0#Column 3;2",
    "differentiator": "Footer3Col-Column3"
  },
  {
    "place": "Content:0#Optional;3|Top Row",
    "differentiator": "Footer3Col-TopRow"
  },
  {
    "place": "Content:1#Optional|Copyright",
    "differentiator": "Footer3Col-Copyright"
  }
]

My incorrect?/incomplete understanding:

1. At first I had this as "Parts" as shown in all the examples. But this left a blank tab called "Content" with nothing in it. ( This answer is how I learned I could change "Parts" to "Content"). I don't really know why/what the difference is though. Are there options to pick from?
2. Not sure what this number does in this case? In some examples this is 0, in some examples this isn't even there, so this is confusing.
3. Modifier for tabs, cards, or columns. can be #, %, or |
4. Name of the tab
5. Tab order
6. Creates a column ON the tab like in this video
7. Name of the column ON the tab
8. Here, changing this number allowed me to order the columns ON the tab.

So, main questions:

• Why are the tabs affecting each other?
• The initial word in "place" (# 1 above) - what does it mean/what are the options?

Note: I realize both of these won't be on the same page in the real world, so one affecting the other likely won't be an issue. But I would still like to know what I am doing so I can do things correctly. Any advice is greatly appreciated!! :)