Dyson DC40 is a mid size upright while the DC50 is a compact one.
DC40 has a wider cleaning path, larger bin, powerful suction, and longer hose.
DC50 is 3 pounds lighter, and features new 2 Tier Radial Cyclones technology to increase airflow, trap microscopic particle, and carbon fiber brush bar that can work on hard floors.

Compare Dyson DC40 and DC50

	Dyson DC50 Animal	Dyson DC40 Origin
Images
Price	$449.99 at dyson.com on July 04, 2014	$399.99 at dyson.com on July 04, 2014
Cyclone Technology Type	2 Tier Radial™ Cyclones	Radial Root Cyclone™ technology
Ball Technology	Yes	Yes
Design	Compact Upright	Mid Size Upright
Multiple Floor Types Cleaning	YES	YES
Corded or Cordless	Corded	Corded
Retractable Cord	No	No
Cord Length	24.9 feet	24.6 feet
Hose Length	8.5 ft	15.3 ft
Max Reach	33.4 ft	40 ft
Wand Type	Instant Release	Instant Release
Amps	6.5 amps	10 amps
Suction Power	128 airwatts	200 airwatts
Suction Control	No	No
Bagged or Bagless	Bagless	Bagless
Bin Size	0.21 gallons	0.42 gallons
Motorized Brushroll	YES	YES
Brush On/Off	YES	YES
Cleaner Head Width	about 11″	about 12.2″
Cleaner Head Technology	Self-adjusting	Self-adjusting
Manual Height Adjustments for Carpet/Rug cleaning	No	No
Weight	11.6 lbs	14.6 lbs
HEPA Filtration	YES	YES
Included Tools	Tangle-free Turbine tool Combination Tool Stair Tool	Combination tool Stair tool
Dimensions	30.1" x 11" x 13.9"	41.9" x 12.2" x 14.3
Warranty	5 year warranty on parts & labor	5 year parts and labor warranty

Here are a few main differences between Dyson DC50 and DC41 that you should consider while deciding between these 2.

New Technologies:
The DC50 features the new Dyson cleaner head that includes a mixture of stiff nylon bristles and anti-static carbon fiber filaments. The carbon fiber bristles can improve the dust pickup on hard floors while the brush bar on DC41 is only intended for carpeted surfaces.
The DC50 features new 2 Tier Radial Cyclone technology to increase airflow and separate more microscopic dust while the DC41 is equipped with Radial Root Cyclone Technology.

Cord & Hose Length:
DC41 has a longer cord that is 35 ft long, about 10 ft longer than the one on DC50. And the DC41 includes a 15.4 ft hose while it’s 8.5 ft long on DC50.

Dust Bin Capacity:
DC41 has a much larger dust bin that can hold 0.55 gallons while it’s only 0.21 gallons on DC50.

Size and Weight:
DC41 is full size while the DC50 is compact, so the DC41 is bulkier, and about 5.5 lbs heavier than the DC50. But DC41 has wider cleaning path, and its suction power is 235 airwatts versus 128 airwatts on DC50.

More details about the specs of DC41 and DC50, read the table below.

Compare Dyson DC41 and DC50

	Dyson DC50 Animal	Dyson DC41 Animal
Images
Price	$449.99 at dyson.com on July 03, 2014	Not Available at dyson.com
Cyclone Technology Type	2 Tier Radial™ Cyclones	Radial Root Cyclone™ technology
Ball Technology	Yes	Yes
Design	Compact Upright	Full Size Upright
Multiple Floor Types Cleaning	YES	YES
Corded or Cordless	Corded	Corded
Cord Length	24.9 ft	35 ft
Hose Length	8.5 ft	15.4 ft
Max Reach	33.4 ft	51 ft
Cord Rewind	Manual	Manual
Amps	6.5 amps	10 amps
Suction Power	128 airwatts	235 airwatts
Suction Control	No	No
Bagged or Bagless	Bagless	Bagless
Bin Size	0.21 gallons	0.55 gal
Motorized Brushroll	YES	YES
Brush On/Off	YES	YES
Cleaner Head Width	about 11″	about 13.3″
Cleaner Head Technology	Self-adjusting	Self-adjusting
Manual Height Adjustments for Carpet/Rug cleaning	No	No
Weight	11.6 lbs	17.1 lbs
HEPA Filtration	YES	YES
Included Tools	Tangle-free Turbine tool Combination Tool Stair Tool	Tangle-free Turbine tool Combination tool Stair tool
Dimensions	30.1" x 11" x 13.9"	41.9" x 12.2" x 14.3
Warranty	5 year warranty on parts & labor	5 year parts and labor warranty
P.S. Dyson DC41 Animal and DC41 Animal Complete is the same except for the color and tool they include, the Complete version comes with more tools, in addition to the 3 tool that DC41 Animal has, it also has a Soft Dusting Brush, Stuff Bristle, Brush, Multi-Angle Brush, and Zorb Carpet Powder.

Overall, the DC50 is better suited for a small house or apartment. For a large house, buy the DC41 instead.

The Dyson DC50 is a newer model that features some Dyson’s new technologies.
New cleaner head with carbon fiber brush adjusts automatically to both carpets and hard floors, and pick up fine dust.
New 2 Tier Radial Cyclone Technology to capture more tiny particles.
New Ball Technology for easier steering into awkward areas.

A quick overview:
Dyson DC25 is more powerful, it has 220 airwatts suction power compared to 128 airwatts on DC50, and it has larger bin, but with a bulkier size, heavier weight.
Dyson DC50 features new technologies, it is compact, about 4.5 pounds lighter, but has smaller dust container, less suction power. And its max reach is shorter since its hose is shorter.
More specs difference between Dyson DC25 and DC50., please read the table below:

Compare Dyson DC25 and DC50

	Dyson DC50 Animal	Dyson DC25 Animal
Images
Cyclone Technology Type	2 Tier Radial™ cyclones	Radial Root Cyclone™ technology
Price	$449.99 at dyson.com on July 02, 2014	Not Available at dyson.com
Movement Type	Ball Technology	Ball Technology
Design	Compact Upright	Full Size Upright
Multiple Floor Types Cleaning	YES	YES
Corded or Cordless	Corded	Corded
Cord Length	24.9 ft	24.6 ft
Max Reach	33.4 ft	40.3 ft
Auto Cord Rewind	No	No
Amps	6.5 amps	11 amps
Suction Power	128 airwatts	220 airwatts
Suction Control	No	No
Bagless	YES	YES
Bin Size	0.21 gallons	0.31 gallons
Motorized Brushroll	YES	YES
Brush On/Off	YES	YES
Brushbar Control Type	Fingertip control	Fingertip control
Cleaner Head Width	about 11″	about 12″
Cleaner Head Technology	Self-adjusting	Self-adjusting
Manual Height Settings for Carpets	No	No
Weight	11.6 lbs	16.125 lbs
Warranty	5 year warranty on parts & labor	5 year parts and labor warranty
HEPA filter	YES	YES
Washable filter	YES	YES
Dimensions	30.1" x 11" x 13.9"	42.4" x 12.2" x 15.4"
Included Tools	Tangle-free Turbine tool Combination Accessory Tool Stair Tool	Mini turbine head for removing pet hair Combination Accessory Tool Stair Tool