TIOBE index

According to the site, TIOBE index is "not about the best programming language or the language in which most lines of code have been written". However the site does claim that the number of web pages may reflect the number of skilled engineers, courses and jobs worldwide.

TIOBE index is sensitive to the ranking policy of the search engines on which it is based. For instance, in April 2004 Google performed a cleanup action to get rid of unfair attempts to promote the search rank. As a consequence, there was a large drop for languages such as Java and C++, yet these languages have stayed at the top of the table. To avoid such fluctuations, TIOBE now uses multiple search engines.

As of August 2016^[update]C reached its lowest ratings score since the index was launched, but was still the second most popular language after Java.

The TIOBE programming language of the year award goes to the language with the biggest annual popularity gain in the index, e.g., Go was the programming language of the year in 2016.

Pierre Carbonnelle challenges TIOBE's naming of Objective-C as the "programming language of the year" in 2012, arguing that there may be many Objective-C pages on the web, but they are rarely read. It proposes its own PYPL index instead, based on Google Trends data. It shows popularity trends since 2004, worldwide and for 5 different countries.

Tim Bunce, author of the Perl DBI, has been critical of the index and its methods of ranking.

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