Widows and Orphans
An orphan is the first line of a paragraph that is left at the bottom of the page (or column) and a widow is the last few words of a paragraph that end up at the top by themselves. In the world of desktop publishing a single line of a paragraph hanging out alone should be avoided whenever possible.
So you are placing type in your document and at the bottom of the page is an orphan. What can you do? The easiest fix is to force the orphan to the next page by inserting a blank line or, if in a program like PageMaker, you would adjust the text bar and move it up to shorten the text column. Some might complain that then there is a white space. White space is okay! But if it really bothers you there are other options.
When faced with a widow, you could do the same thing as for an orphan and force a line of text at the bottom to shift to the top, and then the widow wouldn't be alone anymore. Blank lines between the paragraphs, if any, could have their point size slightly reduced until the widow returns to the rest of the paragraph. Or increasing the point size would force another line to join the widow. This would work for orphans or white space too. If you end up reducing (or enlarging) too much so that the white lines are noticeably smaller (or larger), then this may not be your best choice. Decreasing or increasing the leading between lines of text can work also.
Look to see if any of the paragraphs on the page end with only a couple of words on the last line. If so, then you have two options to play with. Either tighten up the tracking on the last couple of lines to squeeze words together bringing the words on the last line up to join the others, or hyphenate some words that as a whole wouldn't fit on the line above, but part of the word would. This makes the words in the remainder of the paragraph to shift accordingly. Be careful to not squeeze or hyphenate too much making the text difficult to read. Any tweaks you make should not be obviously noticeable.
Some other alternatives include: inserting a quote box or illustration, or resizing one that may already be on the page; adjusting the margins; or editing the text to shorten or lengthen the paragraph, if it is your writing. If it is someone else's writing, be sure to get their approval first.
Although there are many choices available to take care of those pesky widows and orphans, sometimes you may just have to leave them where they are. The main thing to keep in mind is the overall look of your page. It is always a good idea to printout any page you tweaked to make sure everything looks good and is readable!