Is internal mean inside?

Yes, internal means inside, inner, located within something, as opposed to external which means outside. Internal is adjective meaning situated inside, occurring inside, or relating to inner part. For example, internal organs are organs inside body like heart, lungs, liver, as opposed to external features like skin and hair. Internal pain means pain felt inside body, not on surface. In a company, internal meeting means meeting inside organization among employees, not involving outside people. Internal storage in computer means storage inside device, not external drive. In a building, internal walls are walls inside building, not outside walls. Internal can also mean private, confidential, or within, as internal information is information inside organization not shared publicly. So yes, internal essentially means inside, inner, or interior, describing something that is within boundaries of object, body, or system. It comes from Latin internus meaning within. Opposite is external meaning outside. So if you say internal part, you mean inside part, internal area means inside area, internal feelings means feelings inside mind. So internal does mean inside.