There are three kinds of
tyre repair. They can be fixed from the outside using what’s known as tyre string; mended from the inside using a repair patch; and given an internal repair using a combination of a patch and plug for the puncture hole.
However, the external repair is viewed as being very temporary. At best something to get you home, assuming home isn’t at the other end of the country.
Of the three
puncture repair methods, the patch/plug is the only kind of tyre repair that conforms to
British Standard BS AU 159, the minimum suggested safety standard.