There are many reasons why we may be attracted to individuals, from their pheromones to them having a kind smile, but when it comes to being attracted to a 'type' of person our reasoning may be slightly different.
In the first instance we tend to be attracted to the type of person who we think that we may like to know. This means that they seem to be like us in some way, or display traits which we admire and would like to incorporate into our own personality.
When we come across someone who is very different to us we may still be interested in them as a person, but we will be less attracted to them as we share less in common and so have no familiar material with which to share a mutual understanding, and so to start us off on the road to friendship.
We may also be attracted to the type of person who we feel likes us. Everyone loves to be liked, and we tend to be turned off by individuals who openly show their dislike for us, unless we are drawn to such a challenge.
Sexual attraction is a slightly different matter, as we may have a type of person in mind as having potential to become our partner. Some people even go so far as to list the characteristics of an person that they would wish to meet, and purposefully seek such an individual. When they find someone who's personality is a close match to the traits on their desire list, they are automatically attracted to them.
This ties in with another reason we may have for being attracted to a particular type of person. We naturally and automatically become attracted to people who we sense may be able to fulfil our needs. Hence, if we are lonely and could do with a gentle companion, we are likely to be attracted to people who are softly spoken and who seem friendly and warm.
At times we may find people who display familiar behaviours as being comfortable to be around. Even someone who has an accent similar to people where we grew up, if we had a happy childhood, may be attractive to us because of this connection.
Many of us will be attracted to people who we consider to be from a similar background to us. People who share the same cultural or religious background can make us feel at ease. It is comforting to be around people who have similar views and who share an understanding with us.
Finally, we are all attracted to people who make us feel good about ourselves. Even people who end up in unhappy relationships where they feel bad, generally begin their relationship in a positive manner and are attracted to their partner because they feel happy in their company.