1. What is localization?

Localization is the adaptation of a product (software, website, online help, documentation, etc.) from a source language to a target language. It must be rendered linguistically and culturally compatible to the target language. Localization (also known as L10n) modifies a product for clients who live in different countries and cultures. Localization goes beyond translation because it requires cultural adaptation and background information concerning local culture.

2. What is the difference between translation and localization?

Localization is a process beyond translation. Translation is only a part of the localization process. Localization continues after the document translation of a product. The translated text is uploaded to the software application again and graphics are adapted to the needs of target language readers. Changes are made in the user interface, the software is tested and final quality assurance is carried out.

3. What are the differences between globalization, internationalization and localization?

There are many definitions for these terms with broad meanings. Sometimes they are used interchangeably, and this can cause confusion.
In the context of software and websites:

Globalization, means a full adaptation of your website or software for the global market. This term is generally used when commercial, technical and linguistic activities are the subject. 
Internationalization,
is a generalization process for a website or a software to be ready for multilingual use without the need for redesign. This process oiccurs at the design and development stage. 
Localization,
is a linguistic and cultural adaptation process that makes a website or software appropriate for the country or region where it is to be used. 
In short, you internationalize a website before localizing it. Globalization of your website means fully completing a project.

4. What do g11n, i18n and L10n abbreviations mean?

These abbreviations are used for globalization (g11n), internationalization (i18n) and localization (L10n). The figures correspond to the number of the letters between the first and the last letters of the word in question. For example, in “internationalization” there are 18 letters between “i” and “n.”