In the simplest way, the difference between them is speed. E is for EDGE (2.75G), which is an enhanced form of what in old phones used to be called GPRS (2.5 G). It has relatively slow data rates of around 236kbps (1mbps peak speed). But actual usage speeds are often lower. Don't expect to stream a video with E showing on your network bar.
What Is 3G Network & WCDMA?
3G is the next one. It uses WCDMA signalling. The data rates here are comparable to edge but It offers better quality, better latency, lower delay, so making it more suitable for audio, video and streaming services.
Meaning of H, H+ And Their Differences
H is HSPA which stands for high speed packet access. It's an improvement over 3G and is mix of HSDPA (downlink) and HSUPA (uplink). Major changes were done on the radio side which increased the data rates to up to 3 and 7Mbps (in theory, its more). Many Smartphone users in Nigeria will have noticed that H has replaced 3G on their phones
H+ is Evolved HSPA. HSPA was further improved into HSPA+ where new technologies like MIMO antennas were introduced which boosted the data to faster speeds of around 160Mbps downloads and around 15Mbps uploads (the data rate for H+ is generally advertised 21Mbps). H+ shows up on my network screen and although I have never experienced download speeds of greater than 1.3mbps, I find the browsing experience on H+ very satisfactory.
What Is A 4G Network? How Is It Different From 3G?
4G networks have begun to appear across Europe and America, and we can expect the technology to arrive Nigeria soon. I will definitely keep you posted.
Note that if you subscribe to a 3G plan, you have subscribed to all the above network types. Your mobile phone first looks out for cells/towers which are H+ capable; if it fails it tries the lower ones. When 3G is not at all available, the mobile phone falls back to Edge.