In crochet, as one may guess, increasing is the act of making more stitches. However, it is a special kind of addition of stitches. For example, when one crochets a 10 x 10 square, they might say "Well, throughout this project I have increased, as I was constantly making more stitches." This is false because increasing is not simply making more stitches, but making more stitches than there would be if there were one stitch made to each place. Sound confusing? It really isn't.
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The above is a diagram of the first row of single crochets of a piece. It contains 10 stitches (counting the turning chain), and without increasing, all rows would contain 10 stitches. The act of increasing, however, would allow rows in the same piece to contain more than 10 stitches. In this way, different shapes of crochet work can be attained, and when combined with
decreasing, many different patterns can be created.
There are many different ways to increase. One of the easiest is to put more than one new stitch in a place. For a subtle increase, one stitch can be added in the middle of a piece. If you continue increasing in the same place for many rows, the work will eventually create a right angle, a concept utilised in the ripple afghan stitch.
Another way to add a subtle increase is to create an extra stitch at the beginning of the row in the base of the turning chain. To match this increase at the end of the row, simply make an extra stitch in the previous row's turning chain. This creates a smooth, tapered edge on each side.
The final method of increasing is a sudden increase. When you finish a row, create, in addition to your turning chain, additional chains, one for each stitch you wish to add. Then, place stitches in these extra chains and work across your newly widened row. In a work of single crochets, it would look something like this:
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In this case, before starting the third row, five chains were added in addition to the turning chain, and a single crochet was worked in each of them to immediately add five stitches to the piece.
This crochet write up uses crochet symbols.