A dialect is a variation of a standard language spoken by a group of people. Sometimes people who live in the same place share a dialect. Sometimes people who are similar in some other way, such as social class, share a dialect.
There is no absolute difference between a dialect and a language. British English and American English are dialects of English. They differ slightly in spelling, in pronunciation, and in vocabulary. However, they are "mutually intelligible", which means people who speak either dialect can understand the other.
On the other hand, Spanish and Portuguese are now different languages, but historically, Portuguese was a dialect of Spanish. Catalan and Gallego were dialects of Spanish, but today are recognized as languages. They are about as near to Portuguese and to Occitan, respectively, as they are to Spanish.
In past times, travel was difficult. Because of this, dialects developed in quite small regions. In Britain there were dialects in the different parts of the country, and traces of this can be heard today. The Romance languages were dialects of Latin that separated in this way.
Differences in dialects can be found:
- in different words (for example, people who speak British English may go to church and people who speak Scottish English may go to kirk)
- in different pronunciations. Words are written the same way but pronounced differently by different speakers.
- in different grammar (for example, most people who speak English may say I dived, but a few say I dove)
Dialect for Kids. Kiddle Encyclopedia.