In SharePoint out-of-Box, we can’t able to add the internal name for the SharePoint field i.e., Columns. But we can enable that by modifying the Create column page on 12 Hive.

For that we have to modify the FldNew.aspx page, that is available under 12 Hive\TEMPLATE\LAYOUTS folder.

Before modifying, take a copy of that file.

Step 1: Open the file and search for this line,

<INPUT type="hidden" value=<%SPHttpUtility.AddQuote(SPHttpUtility.HtmlEncode(strName),Response.Output);%> name="Name">

Step 2: Replace the above line with the following codes,

<!– Internal Name –>
<TR> 
<TD class=ms-sectionline height=1 colspan=4><IMG SRC="/_layouts/images/blank.gif" width=1 height=1 alt=""></TD></TR>
<TR>
<TD nowrap></TD>
        <TD class="ms-descriptiontext" valign="top">
            <TABLE border=0 cellpadding=1 cellspacing=0>
                <TR><TD height=28 valign=top class=ms-sectionheader id=onetidNewColumnOption><H3 class="ms-standardheader"><SharePoint:EncodedLiteral runat="server" text="Internal Name" /></H3></TD></TR>
                <TR><TD class="ms-propertysheet" id=onetidNewColumnOption2><SharePoint:EncodedLiteral runat="server" text="Type an internal / static name for this column." EncodeMethod=’HtmlEncode’/> <BR/> <BR/></TD></TR>
            </TABLE>
        </TD>
            <TD class="ms-authoringcontrols" width=10>&nbsp;</TD>
            <TD class="ms-authoringcontrols" ID=onetidFldEditGuts2><LABEL for="idInternalColName"><SharePoint:EncodedLiteral runat="server" text="Internal Name" EncodeMethod=’HtmlEncode’/></LABEL><FONT size=3>&nbsp;</FONT><BR>
                <TABLE border=0 cellspacing=1>
                    <TR>
                        <TD colspan=2>
                            <INPUT class="ms-input" title="<SharePoint:EncodedLiteral runat=’server’ text=’<%$Resources:wss,fldedit_columnname%>’ EncodeMethod=’HtmlEncode’/>" type="text" value=<%SPHttpUtility.AddQuote(SPHttpUtility.HtmlEncode(strName),Response.Output);%> name="Name" MaxLength=255 size="<SharePoint:EncodedLiteral runat=’server’ text=’<%$Resources:wss,fldedit_idDisplayNameSize%>’ EncodeMethod=’HtmlEncode’/>" />
                        </TD>
                    </TR>
                </TABLE>
            </TD>
        </TR>

Step 3: Now the page is enable with the internal name. Now we can enter the different name for Internal name and display name on creating a new column.

cheers.