There are several different wireless standards out there and they each have different specifications. Listed below are the standards and their specifications. Standards | Frequency | Speed | Distance | Backwards compatibility | Bands | 802.11a | 5 GHz | 54 Mbps | 150Ft. | | 20Mhz/UNII | 802.11b | 2 GHz | 11Mbps | 300 Ft. | yes | 20MHz/ISM | 802.11g | 2 GHz | 54Mbps | 300FT | 802.11b | 20MHz/ISM | 802.11n | 2GHz/5GHz | 600Mbps | 1200Ft. | 802.11a/b/g | 20/40MHZ | 802.11ac | 5 GHz only | | | | 20/40/80/160 MHZ |

The 802.11a were meant to transmit in three different frequency bands called the Unlicensed National Information Infrastructure (UNII). The 802.11a will operate in less crowded 5MHz UNII bands. The 802.11a will support data rates of 6, 12, and 24 Mbps with a maximum of 54Mbps. 802.11a is not compatible with other 802.11 standards since they use a different RF technology than the 802.11a. The range for an 802.11a can go up to 150Ft. depending on interference.
802.11b can operate at 2.4GHz and supports data rates of 1, 2, 5.5, and 11Mbps. 802.11b can be backwards compatible with the 802.11 data rates of 1, and 2 Mbps. The 802.11b can reach a distance of 300 Ft depending on interference as well and objects blocking the frequency range. The 2.4GHz Ism will have a much more crowded frequency space. The 802.11b works under the ISM band (Industrial, Scientific, and Medical).

802.11g can operate at data rates of 6, 9, 12, 18, 24, 36, 48, and 54mbps. The IEEE requires only the data rates of 6, 12, and 24Mbps the 802.11g is backward compatible and can communicate with the 802.11b or the standard 802.11 since the amendment requires support for both the ERP-DSSS and the CCK. The distance an 802.11g can go is close to 300ft. also depending on interference and objects in the way.
802.11n can support data rates of up to 600Mbps. 802.11n is backward compatible and can communicate with 802.11a/b/g radios. The 802.11n can reach a distance of up to 1200Ft. again depending on interference and objects. The objective of the 802.11n is to increase the throughput in the 2.4 and the 5GHz frequency bands. The 802.11n uses the operation called High Throughput.

The latest of the wireless standards is the 802.11ac. The 802.11ac will have a 6MHz frequency and will be able to communicate with the 2.4MHZ and 5Mhz. the 802.11ac could allow for the 80MHz and 160MHz channels allowing for faster speeds. The goal is to get above 1Gbps in the 802.11ac standard.
The different standards in the wireless technology I believe could be beneficial if maybe thought out a little better but at those times did anyone really know that the wireless technology was going to get so big and spread out like it has? So now I do believe that it is limiting the new technology that is being deployed now and how more companies are going wireless rather than wired. With all the different standards and ranges now the company or will home users will need to make sure they get the same type of wireless AP and routers to get a better and more effective wireless LAN. Now the wireless standards are improving and becoming more compatible with the older standards maybe they will be very beneficial with the wireless LANs that people already have.

Reference:

Wiley, J. (2012). CWNA Certified Wireless Network Administrator. Retrieved from University of Phoenix.
IEEE 802.11ac. (). Retrieved from http://en.wikipedia.org