Broadband phrase  language, in the field of telecommunications and information technology, generally indicates the transmission and reception of information data, sent and received simultaneously in greater amounts, on the same cable or by radio through the use of transmission media and transmission techniques that support and exploit a bandwidth higher than the previous telecommunications systems instead of said narrow-band.

Of this term signals of the theory in the context it is used to indicate the methods which allow two or more signals to share the same transmission line.

In Italian and European legislation there is no official definition of broadband. However, the European Commission uses the term Broadband in another sense that is synonymous with access to the fastest Internet network that provided by a normal dial-up analog modem. It is in fact a typical relative concept of new telecommunications systems than previous or absolute if one compares with each other the most advanced telecommunications systems (eg. Wireless or wired).

In this sense the most typical broadband would be ensured by the connection via optical fibers. However, despite this expression is designed to include the bandwidth of mobile telecommunications systems (eg. mobile phones and smartphones) third generation (3G) with access to the Internet compared to those of second generation (2G) (broadband or wireless broadband mobile radio ), all of whom have still less bandwidth than wired networks in particular optical fiber in a total bandwidth under shared among many users.

Sometimes this term is used as a synonym for a DSL line: more specifically, various types of DSL lines are considered “broadband” in the sense that data and voice are transmitted on different channels (in practice, usually on frequency bands different), but using the same twisted pair, but this identification does not match, as said above, use work in official documents at European level, and even the use of the first operators in the industry. Given the initial definition, one may find that even the analog modems that operate at a higher speed to 600 bits / s are technically broadband, since the number of signals sent per second (baud) is less than the number of bits transmitted always for the second, or if you prefer to any more than a bit corresponding signal. For example, a modem at 2400 bit / s uses four channels at 600 baud.

Instead the optical fiber has the great advantage of also operate in these conditions. A modulation signal with ADSL, over twisted pair or fiber, guaranteeing a good service even if in small towns will spoil a dozen of the 50 pairs of twisted pairs that are to serve the town.

The network maintenance charges in the pair, in a sense, must be opposite to that of construction (or modernization) of the central telephone with fiber-optic cabling, which, however, do not in practice requires no maintenance, neither preventive nor to failure.

In technical telecomunicazionista, the transmission speed in terms of bit-rate is proportional to the bandwidth B of the transmission channel and decays with the distance because of the SNR degradation for the attenuation effect of the useful signal and the increase of the noise introduced from the channel itself. A bandwidth B of wider transmission therefore allows a reduction of this problem in receiving or higher throughput or connection speed.

The spread of broadband is considered to be a factor of economic growth and employment in a country as to reduce the digital divide.

A minimum speed of connection is an indispensable technical requirement for the spread of certain services such as telecommuting, telemedicine, IPTV, conference call, video call, initiating remote activity.

The availability of a broadband connection is almost essential in any workplace that requires an interaction with the outside world via the Internet. Corporate Intranet normally already have high-speed connections, however, can be obtained with their investment company. The availability of a fast Internet connection depends, however, on the investment decisions of third parties, of your provider.

In the presence of a slow connection, it becomes problematic daily operations such as sending a few megabytes file or opening an Internet page that contains only text. Companies not served by broadband suffer a loss of productivity related to the time required to carry out activities that engage much less competitors served by a fast connection.