The wiring in your home is very important. While electricity in homes has been the norm for many decades, there are some homes that have aging or faulty wiring that could cause issues for a homeowner.
Take for example aluminum wiring. At one time this was used in many homes, but the problem is that the risk of loose connections is a lot higher when using aluminum wiring. If the wiring has been worked on and there is a mixture of aluminum and copper wire, oxidation could pose a problem, leading to shorts or even possibly a fire.
Another, even older, type of wiring is knob and tubing. This has not been used in many decades. Some homes with this type of wiring might have parts of it retrofitted to more modern standards, or it might still be in use. To replace this, you will need the help of an electrician that is experienced, since mistakes could lead to electrocution or a fire hazard.