 So in order to have a basis for the rest of this class, it's important to talk about the parts of a mark record. There are four different parts of a mark record. The record structure and the data content are basically parts that the cataloger doesn't have to worry about too much. There are things that the computer uses to interpret the record. The content designation is what we're mostly going to focus on. And the content designation is the stuff in the record basically. The stuff that tells the computer what is in each area of the record. And there are two different types of content designation, the variable fields and the fixed fields. In this video we are going to talk about the variable fields. These fields contain specific pieces of information. Generally they're pretty much free text where the cataloger creates what's put into them. You don't have to choose from a predetermined set of options. And the variable fields contain four different pieces of content that we'll talk about. They're identified by tags, indicators, delimiters and subfield codes. Tags are three digit numbers that you'll see at the beginning of each line in a mark record. Tags basically tell the computer what type of information is in each field. And I should back up a second and say that a field is basically a piece of information in the record. I've been using that word without defining it. And basically it's just one chunk of information in the record. So the tags tell the computer how to interpret each field. So for example the 245 tag tells the computer that this is a title and statement or responsibility. So you can see right there that 245 is called a tag in this instance. The next piece of variable content are indicators. And they are digits or blanks that give the computer kind of extra information about how to deal with the data contained in the field. The tag tells the computer generally what the information is, but some tags have indicators that are defined to tell the computer how to deal with this. For example, there are two indicators of one and a zero for this particular 245 field. And we will talk about this in more detail in the coming weeks. But the first one, the indicator one tells the computer that there is an author main entry for this record. And the second indicator is a zero. And that tells the computer that you don't need to skip any characters at the beginning. If there is an a, an, or the article at the beginning of the title, then the computer would need to skip those characters in order to alphabetize the title correctly. But in this case it doesn't need to skip anything, so the second indicator is a zero. One thing I wanted to point out is that generally when you're referring to indicators, they're mentioned separately, so you'll say that this has indicators of one zero. It doesn't, you don't say ten, just wanted to point that out. The next piece of content designation we're going to talk about are delimiters. And they basically tell the computer where each subfield starts. Now a subfield is a smaller piece of information within a field. So for example, here in this field we have a title, we have a subtitle, and then we have the author's name and the statement of responsibility. And each of those are a smaller piece of information and they go in a subfield. Delimiters are basically symbols that telecomputers where each subfield starts. You can see different symbols, dollar signs, pound signs, the double daggers, for example. In this class we're going to use the dollar sign to represent a delimiter. And then after a delimiter you'll see a subfield code. And this indicates what type of information is in a subfield. So for example, in this 245 field, subfield A is the title proper, subfield B is the remainder of the title, basically in this case a subtitle, and then C is the statement of responsibility, in this case the author's name. So those codes are important to the computer. They tell the computer what smaller piece of information is contained in each subfield to make up this 245 field. In the resource handout that is at the top of the course webpage, you will see a link to the OCLC bibliographic formats and standards, and I highly recommend consulting that as a place for information about the tags as you go through this course. You will see that all the subfields are listed here, and some of them have R after them and some of them have NR after them. The ones with R means that they're repeatable. You can use them more than once within a given field. The ones with NR means that they are not repeatable. One thing to notice about mark tags is that they are organized by hundreds basically, and sometimes when you hear catalogers talk, their shorthand will be kind of, they'll talk about the 1xx fields or the 6xx fields, and basically any tags that all start with the same first number, they're roughly used for a similar purpose. They are one of these main categories here. Another way to think about mark tags when you're looking at them is that tags that end with the same two numbers have the same type of content. This is called parallel content, and so if you see a tag that ends with 0, 0, whether it's a 100 or a 600 or a 700, you know that's going to be a person's name. If you see a tag that ends with a 1, 0, whether it's a 110, a 610, or a 710, that's going to be a corporate name, and we're going to talk about all these more detail later, so don't worry about that, but this is the concept of parallel content. This also applies to subject headings. Anything that ends with a 5, 0 is a topical term, for example, or anything that ends with a 5, 1 is a geographic term. So the organization by hundreds and the concept of parallel content are two ways of thinking about the organization of mark tags.