NSAIDs and opioids fall under the broad category of analgesic. Analgesics used for pain relief may be simple, compound or topical.
Simple Analgesics
Often available over-the-counter (OTC), simple analgesics contain one type of pain medication and are prescribed to treat mild to moderate pain. These include NSAIDs such as ibuprofen or aspirin. They also include other pain-relieving medications such as Tylenol. Stronger analgesics are available for moderate to severe pain, but often require a doctors prescription. These include opioids such as morphine.
Compound Analgesics
Compound analgesics are pain medications that contain more than one ingredient. Typical combinations include paracetamol and codeine, or paracetamol and oxycodone. These pain medications are usually available by prescription only, because they often contain opioids.
Topical Analgesics
Topical analgesics are applied to the skin to reduce pain and swelling. There are a wide variety of topical analgesics available for pain control, both in prescription and over-the-counter form. These include patches, creams and lotions. Like simple analgesics, topical analgesics can work in a few different ways. Some contain NSAIDs which help target swelling at the site of injury and provide pain relief. Others, such as capsicum, act as skin irritants, countering the feeling of pain.
Source:
Bandolier. Topical Analgesics Introcduction. Accessed 4/7/09. http://www.medicine.ox.ac.uk/bandolier/booth/painpag/topical/Topintro.html

