PHP was my very first language, which in hindsight was probably a good choice for a couple reasons: 1. It's used in a ton of web applications. It's slightly le

PHP was my very first language, which in hindsight was probably a good choice for a couple reasons: 1. It's used in a ton of web applications. It's slightly less popular than in the past due to the influx of frameworks like Rails and Django, but a lot of major web software (Wordpress, Drupal, Joomla, MediaWiki, phpBB) still uses it. 2. People tend to write very insecure PHP code, especially when they fail to use a framework. Again, this is slightly less true now than it was in the past. However, it's very common to see bad practices like: - SQL queries generated via string concatenation - Output escaping done manually, on a per-element basis, rather than in an automatic, context-sensitive manner. - File upload scripts that let you upload PHP files, or file download scripts that accept a filename but don't sanitize against directory traversal attacks.