VersionTracker

VersionTracker.com is a website that tracks software releases. It started out originally as a Mac OS software tracker, eventually expanding into Mac OS X, Microsoft Windows and Palm OS.

VersionTracker does not host the majority of the software listed (it merely links to them), only in special agreements with the developers.

VersionTracker also offers a software called VersionTracker Pro that checks software versions on a user's computer and then queries its database to see if any updates are available. This feature is available only to paid subscribers. Browsing and searching the database is free.

Data extraction

Data extraction is the act or process of retrieving (binary) data out of (usually unstructured or badly structured) data sources for further data processing or data storage (data migration). The import into the intermediate extracting system is thus usually followed by data transformation and possibly the addition of metadata prior to export to another stage in the data workflow.

Usually, the term data extraction is applied when (experimental) data is first imported into a computer from primary sources, like measuring or recording devices. Today's electronic devices will usually present a electrical connector (e.g. USB) through which 'raw data' can be streamed into a personal computer.

Hierarchical model

In a hierarchical data model, data is organized into a tree-like structure. The structure allows repeating information using parent/child relationships: each parent can have many children but each child only has one parent. All attributes of a specific record are listed under an entity type. In a database, an entity type is the equivalent of a table; each individual record is represented as a row and an attribute as a column. Entity types are related to each other using 1: N mapping, also known as one-to-many relationships. The most recognized example of hierarchical model database is an IMS designed by IBM.

Data quality

1. Data Quality refers to the degree of excellence exhibited by the data in relation to the portrayal of the actual phenomena. GIS Glossary

2. The state of completeness, validity, consistency, timeliness and accuracy that makes data appropriate for a specific use. Government of British Columbia

3. The totality of features and characteristics of data that bears on their ability to satisfy a given purpose; the sum of the degrees of excellence for factors related to data

Image spam

Image spam is a kind of E-mail spam where the message text of the spam is presented as a picture in an image file. Since most modern graphical E-mail client software will render the image file by default, presenting the message image directly to the user, it is highly effective at circumventing normal E-mail filtering software.

The basic rationale behind image spam is that it is difficult to detect using spam filtering software designed to detect patterns in text in the plain-text E-mail body. Attempts to filter text in image spam are easily defeated because optical character recognition of text in image spam can be prevented using a variety of obfuscation techniques which will not prevent the spam image from being read by human beings. This is the same phenomenon exploited by CAPTCHAs, but put to the ends of spammers, rather than to deter their activity.