 Male condoms are usually packaged inside a foil or plastic <unk> , in a rolled @-@ up form , and are designed to be applied to the tip of the penis and then <unk> over the erect penis . It is important that some space be left in the tip of the condom so that semen has a place to collect ; otherwise it may be forced out of the base of the device . After use , it is recommended the condom be wrapped in tissue or tied in a knot , then disposed of in a trash receptacle . Condoms are used to reduce the likelihood of pregnancy during intercourse and to reduce the likelihood of contracting sexually @-@ transmitted infections ( STIs ) . Condoms are also used during <unk> to reduce the likelihood of contracting STIs . 
