There can be a number of reasons to learn another language -
It takes time, perseverance and patience to master a new language, but it can be done at any point in your life. You may not become as fluent as a native speaker, but you will be able to speak, think, read and listen in that language. Certainly enough, if you make the effort, to make yourself understandable to a native and understand what the natives are saying in your turn.
Some of us grow up in a multi-lingual environment and can speak two or more languages with easy proficiency. But even if you only know one language, you already have had the experience of learning that one. Learning a new one won't be as difficult as you think it would be.
A language or languages similar to the ones you already know will have many basic concepts in common -
- Similarities in alphabet
- Similarities in vocabulary.
- Similarities in grammar
- Similarities in sentence construction
- Similarities in writing script
- Similarities in sound and pronunciation
For example, if you know English, it will be easier to pick up other European languages having the same alphabet and writing script, like German, Swedish, Danish, Norwegian, Dutch, French, Italian, Spanish and Latin.
It might require somewhat more effort to learn languages like Hindi, Marathi, Urdu, Arabic, Hebrew, Chinese, Japanese, Korean and Russian as these have completely different alphabets and writing scripts. In addition, some of these languages are not written in the left to right manner. Arabic and Hebrew are written from right to left; Chinese, Japanese and Korean are also written from right to left and from top to bottom in vertical columns.
However common points can be discovered with both related and completely unrelated languages. Words have always been exchanged and adapted between languages. Like the French borrowing from the English and vice versa. Or English words finding their way into the Hindi or Japanese lexicon and vice versa. Many English words like bungalow and shampoo originally came from Hindi.
On the other hand, some sounds in the foreign language may not exist in your native one. You may find these sounds difficult to pronounce or articulate at first, but, with regular practice, you'll be surprised how familiar they soon start sounding.
Some sounds that are familiar may not have the familiar meaning. Like the English 'rope' and the Marathi 'rope'. Both are pronounced in the same way, but have completely different meanings. The English 'rope' means rope and the Marathi 'rope' means sapling.
Then there is the issue of differences in cultural etiquette. In English, the pronoun 'you' applies whether you are talking to a child, an adult, a pet, a friend, a relative or a stranger. In Hindi, you may use 'Tum' for familiar persons, but it is more polite to use 'Aap', especially with seniors, acquaintances, business colleagues and strangers. In German, there is the formal 'Sie' and the familiar 'Du'.