SPECS:
1 (2 Cores)64-Bit
68027464
25655069
28355721
30495556
6111258
1.6 GHzCore i5 (I5-5250U)
Details:This model is powered by a 14 nm, 64-bit "Fifth Generation" Intel Mobile Core i5 "Broadwell ULT" (I5-5250U) processor which includes two independent processor "cores" on a single silicon chip. Each core has a dedicated 256k level 2 cache, shares 3 MB of level 3 cache, and has an integrated memory controller (dual channel).

This system also supports "Turbo Boost 2.0" -- which "automatically increases the speed of the active cores" to improve performance when needed (up to 2.7 GHz for this model) -- and "Hyper Threading" -- which allows the system to recognize four total "cores" or "threads" (two real and two virtual).

Also see: How fast are the "Early 2015" MacBook Air models compared to the 12-Inch Retina MacBook and 13-Inch Retina MacBook Pro at the time the MacBook Air was introduced?
2.7 GHz2.2 GHz (Core i7)
SolderedIntegrated
OPI*1.6 GHz (Built-in)
EFI64-Bit
32k/32k x2256k x2, 3 MB (on chip)
LPDDR3 SDRAM*1600 MHz
Details:*Shipped standard with 4 GB or 8 GB of 1600 MHz "Low Power" LPDDR3 SDRAM onboard.
4 GB, 8 GB*8 GB*
Details:*4 GB or 8 GB of RAM is onboard. When first released, it shipped with 4 GB of RAM by default and could be upgraded at the time of purchase to 8 GB as a US$100 option, but it cannot be upgraded later. Starting April 19, 2016, it was configured with 8 GB of RAM by default and could not be upgraded further at the time of purchase or otherwise.

Also see: Actual Max RAM of All G3 & Later Macs.
4 GB, 8 GB*None
HD Graphics 6000Integrated
Details:This model has an Intel HD Graphics 6000 graphics processor that shares memory with the system.
1.5 GB1.5 GB
13.3" Widescreen1440x900

DISPLAY:

 1 (Thunderbolt 2) None
Details:This model is equipped with one Thunderbolt 2 port. Thunderbolt 2 is backwards-compatible with Thunderbolt and Mini DisplayPort-equipped displays as well as adapters that are compatible with Mini DisplayPort (DVI, VGA, dual-link DVI and HDMI). It also can support other peripherals that use the Thunderbolt or Thunderbolt 2 standard.

In the US (and many other countries), site sponsor Other World Computing sells Thunderbolt docks and external drives compatible with this Mac and just about all others.

Also see: What is "Thunderbolt"? Is it an industry standard? What advantages does it offer? Are there any disadvantages?
 None None
 None None
 2 (3.0) None
Details:Two USB 3.0 ports (up to 5 Gbps).

Also see: What is the best USB 3.0 hub to use with the MacBook Air while traveling?
 None None
Details:No internal modem or Ethernet. External Apple Thunderbolt to Gigabit Ethernet adapter offered for US$29.
 None None
 2 (Internal) None
 None* 1*
 None None
 N/A 1