Many jurisdictions outlaw not only firearms, but also knives, pepper spray, mace, and expandable batons, or any other tool which the powers that be deem too dangerous for your use.
On the other hand, many common household items can serve double-duty as improvised weapons — and these won’t get you into trouble with law enforcement.
Weapons do damage by blunt force, slashing, or piercing.
Slashing weapons are anything with a sharp edge. Improvised weapons in this category consist mostly of kitchen knives. I do not recommend focusing on slashing weapons because 1) they are difficult to make look innocent, 2) they require skill and practice, 3) they tend not to have enough reach, and 4) it can be hell to clean up afterwards.
Piercing weapons can be a bit better, if you pick one that has greater range. Any long stick can be a piercing weapon. It’s nice if the stick has something sharp on the end, but even a round-tipped broom will cause hell with an opponents internal organs if you strike vigorously anywhere in the abdomen. A stury umbrella can be used as a piercing weapon, but it is quite difficult to find an umbrella that is sufficiently study. Short-range piercing weapons like car keys are sometimes better than nothing.
Bludgeoning weapons are the best and most common improvised weapons. A 4D cell Maglight is an excellent tool for encouraging civility. The smaller 2AA cell tactical flashlights which are now popular can be very effective weapons when you hold them tightly and strike with the side of your fist. Keeping a nightstick or tonfa in your car might cause legal trouble, but a baseball bat seldom arouses suspicion. Adding a glove and a ball perfectly disguises your purposes. If you really haven’t had the opportunity to prepare, almost anything can be used as a bludgeoning weapon. It’s hard to beat a chair as a defensive weapon. A beer bottle can be grasped by the neck and used as a small club.
Slashing weapons can be used on any area of exposed of lightly covered skin. In addition to targeting the body, it can be very useful to target the hands and the forearms. Most people put those out in front of themselves unprotected, just begging for them to be slashed. Slashing an opponents forearm can distract them quite effectively.
With piercing weapons, you’ll usually want to target large soft areas — usually the abdomen. It is too difficult strike smaller targets with a piercing blow. The abdomen makes a good target because it tends to move more slowly than the arms, legs, or head.
With bludgeoning weapons, you will want to aim for joints or for the skull. A strike on a knee or elbow can effectively put an opponent out of the fight. Even a hard knock across the back of the hand can discourage many opponents. When striking the head, try for the nose or the temples.
Legality of Use
When you defend yourself with an improvised weapon, be prepared to defend yourself again — in court — against a charge of assault with a deadly weapon. Any good weapon can kill, and you may need to use you need to use your improvised weapon for maximum effect.
A lot of “self defense experts” advise people to run from fights. I wonder how many real fights those guys have been in. My street fights have often involved protecting a smaller or less skilled person from being attacked — which precluded running from being an option. Even in cases where I was alone, in most cases running away would simply have caused myself to be chased down by a group of violent opponents. Attempting to run away would simply have meant that I would have had to fight tired — and with my back to my opponents.
Nonetheless, if you do find yourself in one of those situations where both the moral and tactical factors allow you to run away, you might save yourself both jail time and legal fees. I have many stitches and scars from street fights which I was unable to avoid. This is not what you want for yourself. This is one of those situations where it is best to live vicariously through others. Running away might also include apologizing or handing over your wallet. Apologizing is free and a good lawyer will cost you far more than the contents of your wallet.