Languages can change over time. The form of English that you speak is likely to be slightly different to the form of English that your parents — or grandparents — speak. For example, you may pronounce some words differently from them or there might be some words that you've heard of that they haven't (and vice-versa).
Many people underestimate the extent to which languages can change. To give you an idea, here is the Lord's Prayer as it might have been written in the English that was spoken about 1000 years ago (called Old English):
- Fæder ure þu þe eart on heofo
- Si þin nama gehalgod.
- To becume þin rice,
- Gewurþe ðin willa,
- On eorðan swa swa on heofonum.
- Urne gedæghwamlican hlaf syle us todæg,
- And forgyf us ure gyltas,
- Swa swa we forgyfað urum gyltendum.
- And ne gelæd þu us on costnunge,
- Ac alys us of yfele. Soþlice.
Here's the version as it might have been written about 650 years ago (called Middle English):
- Oure fadir þat art in heuenes,
- Halwid be þi name.
- Þi reume or kyngdom come to be,
- Be þi wille don,
- In herþe as it is doun in heuene.
- Yeue to us today oure eche dayes bred,
- And foryeue to us oure dettis þat is oure synnys,
- As we foryeuen to oure dettouris þat is to men þat han synned in us.
- And lede us not into temptacion,
- But delyuere us from euyl. Amen.
- Our Father who art in heaven,
- Hallowed be thy name.
- Thy kingdom come,
- Thy will be done,
- On earth as it is in heaven.
- Give us this day our daily bread,
- And forgive us our trespasses,
- As we forgive those who trespass against us.
- And lead us not into temptation,
- But deliver us from evil. Amen.
Language families and proto-languages
As languages change, the people who speak them sometimes split up into groups and travel apart from each other. Since there is usually very little contact between these groups, the languages that they speak often change in different ways to each other. This forms a family of languages that all came from a common source.
A proto-language is the ancestor of other languages.
Adding history to a conlang
If natural languages change over time, then why not make your conlang change over time to? You could invent a whole family of languages that all came from the same source. Note that it is easier to invent a daughter language for a known, or previously invented, mother language than vice versa. This section on history will help you to do this.