sanskrit is the oldest language and it is still in use in HINDI rituals
Sanskrit
The Greek Alphabet is the oldest one that is in common use, around the world. But Greek is no longer spoken. Tamil is an ancient language, used primarily in the Sub-Continent of India, which is still spoken today (however by a very few number of people).
Aspirin is the oldest OTC analgesic in common use.
It is the oldest NATIONAL flag still in use - it is not the oldest flag.
The oldest computer language still in use is Fortran, invented in 1957. The first computer language was assembly language, but the first high level programming language was Plankalkul.
No. The Chinese language has evolved over time. For example, this is the oldest version of horse: ANd here is the new one: Also, there are a few versions in the middle. But the words are still the same.
Copper
Sterling
tye
Lambeau Field
COBOL = COmmon Business-Oriented Language. Although it is one of the earliest high-level computer languages, it is still in use today, albeit employing modern programming features including object-oriented programming methods. The latest stable release is getting on for some 10 years old now while OpenCOBOL is perhaps the most common implementation.
You use that person's language, if you know it, or you use a common language that you both know - even if only slightly. If you have no language in common, use hand gestures and drawings to convey your meaning.