ArcGIS tip-- joins and relates

Joins and relates are a way for you to add data to an already existing feature class file. For example, you might have a polygon that you want to assign the value of 100 to... or you might have points that represent the location of birds, and you want to give the number of birds.

How to do this?
First you are going to want to put the information you want to assign into an Excel file as a column vector.
Next to that vector, you want to replicate at least one vector from your pre-existing Feature class file:

See the column I wanted to add (above) is "prod" and one line of information from my feature class (already on the map) is "OBJECTID_1".  It's crucial you title this column EXACTLY THE SAME as the column in your data. It makes it easier. Sometimes it will work if different, but this helps me stay organized.

Now in Arc, right click on your feature and you'll get a pop up window for "joins and relates"

You can either use a join or a relate. Joins are more permenant; relates sometimes go away. But joins are more taxing on the computer and relates are not. So my advise is-- use relates to figure out what you want, and then join.

So in the first blank (not the drop down, but the number 1) you will choose your pre-existing feature class on your map.  In the second one, navigate to your excel file.

REMEMBER 2 things: Arc hates finding things that it is not "connected to"- connect to that drive, at least, using ArcCatalog. Arc likes Excel files more than CSV's or TXT. Titles make Arc happy! So .xlsx WITH TITLES is the way to go.

In the third blank, choose the OBJECT ID or other column that you named the same as the column in the map. OK will light up.

Now wait and pray.

OKAY! There's your data, imported, maybe labeled if you want. That's the end!