Because sewing was required for the construction and repair of the Tabernacle it falls under prohibited acts.
The definition of sewing involves the uniting of two items into one and is not limited to the specific use of a needle and thread to connect strips of fabric. The prohibition extends to all types of mending including gluing and taping and includes all materials: leather, paper, soft plastic and wood.

The Biblical definition of sewing is the act of drawing a thread back and forth between two pieces of fabric three or more times or so that both ends of the thread emerge on the same side of the fabric and are tied in knots.

The melachah of sewing is distinct from that of tying a knot but both share the common aim of fastening.

Fastening two items by tightening a thread that connects them loosely is prohibited.   Use of a safety pin is generally considered akin to sewing. A distinction is however made between pinning temporarily and permanently and use in cases where the pin is inserted only once and remains visible (the pin must be removed within twenty-four hour time period).

Since the definition of sewing is the uniting of two items or parts into one, gluing and taping are likewise forbidden.  Rabbinic authorities differ in the application of this rule to disposable diapers since the diaper is unfastened well within twenty-four hours of securing the item on the child.  One should be careful not to secure the adhesive to the sides of the diaper where they will become permanently affixed when disposing of the diaper.

Stapling is a form of sewing and is forbidden. According to some authorities, closing wounds with sutures is a forbidden act.  In cases where it is a necessity a Halachic authority should be consulted.  Band-aids are permitted so long as they will be removed within a short time but care should be taken not to fasten one band-aid to another.

Adapted from The Shabbas Home by Rabbi Simcha Bunim Cohen